In 1961, the Men in Black (MIB) organization was founded after secretly making first contact with extraterrestrials. The MIB designates Earth as a neutral zone for alien refugees who live in secret among humans. Agents monitor alien activity and use memory-erasing neuralyzer devices to maintain secrecy. In 1997, MIB Agents K and D disrupt a border patrol operation at the Mexico–United States border to capture a Samurian named Mikey. When Mikey becomes violent, K uses a MIB gun to kill him and neuralyzes the patrol officers. D, feeling too old to continue, asks K to neuralyze him so he can retire. Soon after, NYPD officer James Darrell Edwards III apprehends a suspect, unaware that he is an alien. The alien warns of a coming threat before committing suicide. K, impressed by James' performance, recruits him into the MIB. After completing a series of tests, James becomes Agent J, and his previous identity is erased from public records. Meanwhile, a hostile alien known as a "Bug" crash-lands in upstate New York. The Bug kills a farmer named Edgar and uses his skin as a disguise. K and J, tipped off by a tabloid news article, question Edgar's wife. They learn that the Bug has killed two aliens who were living on Earth in disguise. Their bodies, along with their pet cat, are sent to a morgue overseen by coroner Laurel Weaver. At the morgue, the alien tells J and Laurel that "the galaxy is on Orion's Belt " before dying. After neuralyzing Laurel, K identifies the alien as Rosenberg, a prince from the Arquillian Empire. K and J visit Frank the Pug, an alien informant, who explains that Rosenberg was protecting a miniature galaxy. The galaxy is a powerful energy source that the Bug wants to use to destroy the Arquillians. An Arquillian warship soon arrives in Earth's orbit and demands that the MIB return the galaxy, or they will destroy the Earth. J and the Bug both realize the galaxy is on the collar of Rosenberg's cat, Orion, which is now with Laurel. The Bug captures her and swallows the galaxy. As the Arquillians prepare to destroy Earth to stop the Bug, the MIB locks down all transportation. J guesses the Bug will head to the New York State Pavilion, where the MIB hid flying saucers during the 1964-65 World's Fair. At the site, the Bug tries to escape with Laurel, but she briefly breaks free. K and J shoot down the ship, which crash-lands in Corona Park. The Bug sheds his human skin, revealing his true form and swallowing the agents' weapons. K allows himself to be eaten so he can retrieve his weapon from inside. J distracts the Bug until K shoots the Bug apart from within. Laurel uses J's gun to finish the Bug off. After returning the galaxy to the Arquillians, K reveals that he was training J to take his place. J neuralyzes him so he can retire. Later, J continues his work with Laurel, who has joined the MIB as Agent L.

FBI Special Agent Sean Archer survives an assassination attempt by Castor Troy, a terrorist-for-hire, but the bullet kills his son Michael. Archer then engages in an extended vendetta against Troy. It culminates, six years later, in his team ambushing Troy, who is with his younger brother and accomplice, Pollux, on a remote desert airstrip. Castor goads Archer by saying he knows of a bomb that is located somewhere in Los Angeles and is set to explode in a few days. Before Archer can learn more, Castor is knocked unconscious and falls into a coma. Pollux, in custody, affirms that the bomb is real but refuses to reveal its location. In secret, Archer reluctantly undergoes a highly experimental face transplant procedure by Dr. Malcolm Walsh to take on Castor's face, voice, and appearance. Archer-as-Castor is taken to the same high-security prison where Pollux is being held in order to obtain information on the bomb's location. Castor unexpectedly awakens from his coma and discovers that his face is missing. He calls his gang, and they force Dr. Walsh to transplant Archer's face onto him. Meanwhile, Archer successfully learns the bomb's location from Pollux before being informed that he has a visitor. Anticipating a reunion with his colleagues and a return to his normal life, Archer instead finds Castor wearing his face. Upon revealing he has murdered everyone else who knows about the face transplant, Castor gleefully informs Archer that he looks forward to ruining his FBI career and ravishing his wife. Pollux is freed when he willingly tells Castor-as-Archer of the bomb's location, and Castor subsequently disarms the bomb. Castor earns admiration from the FBI office and becomes close to Archer's wife Eve and daughter Jamie, whom Archer had been neglecting while seeking to avenge the death of his son. Back at the prison, Archer-as-Castor escapes after staging a riot and retreats to Castor's headquarters. There, he meets Sasha, the sister of Castor's primary drug kingpin Dietrich Hassler, and her son Adam, who reminds him of Michael. Archer discovers that Adam is Castor's son. Castor learns of Archer's escape and hastily assembles a team to raid his headquarters. The raid turns into a bloodbath, and many FBI agents and several members of Castor's gang, including Dietrich and Pollux, are killed. Archer-as-Castor, Sasha, and Adam all manage to escape. In the aftermath of the raid, Archer's supervisor, Director Victor Lazarro, angrily lambasts Castor-as-Archer for the unnecessary bloodshed he caused. Castor, still furious over Pollux's death, murders Lazarro and is subsequently promoted to acting director in his place. Meanwhile, after taking Sasha and Adam to a safe location, Archer-as-Castor approaches Eve and convinces her to test Castor-as-Archer's blood to confirm his identity. After testing the blood and being convinced that the man wearing her husband's face is in fact an imposter, Eve tells Archer that Castor will be vulnerable at Lazarro's funeral. At the ceremony, Castor-as-Archer has taken Eve hostage. Sasha arrives, and a gunfight ensues; Sasha manages to save Eve after taking a bullet. Archer-as-Castor promises a dying Sasha that he will take care of Adam and raise him away from criminal life. Castor briefly takes Jamie hostage, but she escapes by stabbing him with the butterfly knife that he lent her earlier for self-defense. Following the confrontation at the church, Castor reaches the docks and commandeers a speedboat while Archer commandeers one of his own to continue the pursuit. The chase ends when Archer forces Castor to the shore in a collision. With their boats grounded, the two proceed to fight to the death. Upon gaining the upper hand in the struggle, Archer manages to corner Castor at gunpoint with a speargun, only for the latter to prevent him from shooting by grabbing the firing mechanism. While admitting defeat, Castor tries to disfigure his face so that Archer will be doomed to wear the former's face forever. Before he can finish, Archer kicks Castor in the groin, causing him to lose his grip on the gun and allowing Archer to finally kill him. Backup agents arrive and address Archer-as-Castor by his true name, having been convinced by Eve of Archer's identity. After the face transplant surgery is reversed, Archer returns home. He and Eve adopt Adam, keeping Archer's promise to Sasha.

LAPD SWAT bomb disposal officers Jack Traven and Harry Temple are tasked with preventing a bombing on a city elevator containing 13 people, planned by an extortionist, Howard Payne. After narrowly rescuing the passengers, the duo hunt down Payne, during which Harry is wounded to stop Payne from taking him hostage. Payne seemingly blows himself up, and Jack and Harry are later commended in a ceremony for their bravery. It is revealed that Payne had faked his death, and has become personally bitter towards Jack. After destroying a city bus to get Jack's attention, Payne contacts him with a new scheme: a bomb planted on a second city bus (a 1966 GMC New Look) that will activate upon reaching 50 mph (80 km/h) and detonate if the speed goes below 50, but is also set to go off sometime before noon. He warns Jack not to offload passengers or the bus will explode. Jack receives a demand from Payne: $3.7 million in ransom or the bomb will explode. Racing through traffic, Jack gets a ride in a Jaguar from Maurice to warn the bus driver of the bomb. Realizing the bus has surpassed 50 mph and the bomb is armed, Jack boards the bus, but a felon's panic leads to the driver, Sam, being shot. A passenger, Annie Porter, takes over driving. With the bomb armed and passengers aware of the threat, Jack contacts Harry for help while trying to keep the bus moving. Payne agrees to allow Sam to be offloaded as a sign of good faith. A passenger, Helen, panics and attempts to get off the bus, but Payne detonates a smaller bomb, causing her to fall out and be killed. Despite Payne's constant surveillance, Jack and Annie maneuver the bus through several dangerous obstacles, including a gap in the freeway, and direct it to Los Angeles International Airport to avoid traffic-congestion. Meanwhile, Harry discovers that Payne is a former Atlanta Police Department bomb squad officer who was placed on administrative leave after losing a thumb. The bomb's design reflects his long-lasting bitterness over being under-compensated with nothing but a "cheap gold watch". Harry leads a SWAT team to arrest him; however, Payne's house has been rigged with explosives, and Harry and his teammates are killed in the blast. In a last-ditch effort to defuse the bomb, Jack goes under the bus on a tethered roller bed, but the cable snaps. He is helped onboard by the passengers. In the process, he punctures the fuel tank and the bus starts leaking gasoline. Jack admits defeat until he notices that Payne is monitoring the bus interior with a hidden surveillance camera. With the help of a television crew, the LAPD tamper with Payne's surveillance footage. This gives Jack enough time to help the passengers escape before the bus crashes and explodes into a cargo plane. While noticing the LAPD has dropped-off the ransom and is waiting to apprehend him, Payne sees the tampered video feed and seeks revenge. The SWAT team are waiting for Payne to appear, but Payne kidnaps Annie while impersonating a police officer. Jack discovers a hole under the trash can, where Payne has taken the ransom and accessed the subway system. Jack finds Annie wearing an explosive vest; after a confrontation between Payne and Jack, Payne escapes on a train with Annie. Payne shoots the driver and train controls. He opens the duffel bag containing the money and a dye pack explodes in his face. An enraged Payne fights Jack on the train roof, only to be decapitated by a passing overhead signal when Jack pushes him to the roof of the tunnel. Jack deactivates the vest from Annie, but finds that the train cannot be stopped. Jack instead accelerates the train, causing it to derail and crash onto Hollywood Boulevard, and screeches to a halt in front of a tour van. Jack and Annie emerge unscathed and share a kiss as onlookers watch in amazement.

In 1967, a visit by the Shah of Iran to West Berlin leads to a clash between the West German student movement and German police. In the chaos, unarmed protestor Benno Ohnesorg is fatally shot by policeman Karl-Heinz Kurras, outraging the West German public, including left-wing journalist Ulrike Meinhof, who claims in a televised debate that West Germany is a fascist police state. Inspired by Meinhof's rhetoric, radical communists Gudrun Ensslin and Andreas Baader mastermind the Frankfurt department store firebombings of 1968. While covering their trial, Meinhof is moved by the radicals' commitment and befriends Ensslin during a prison interview before leaving her husband for radical-linked journalist Peter Homann. Left-wing activist Rudi Dutschke is injured in an assassination attempt by neo-nazi Josef Bachmann, further radicalizing the Left. Ensslin and Baader are released pending an appeal and recruit youths, including Astrid Proll and Peter-Jurgen Boock, to their cause. After spending some time abroad, Baader, Ensslin, and Proll move in with Meinhof, who begins advocating violent action but does not wish to leave her two children. When Baader is arrested again, Meinhof arranges an "interview" off prison grounds, which Ensslin and the others use to break him out; though the plan called for Meinhof to appear innocent and stay behind, she flees with the radicals, incriminating herself. Meinhof sends her children to Sicily and the group receives guerilla training from Fatah in Jordan. Homann, overhearing the others asking Fatah to kill him and Meinhof planning to recruit her children as suicide bombers, leaves the group and arranges for his colleague Stefan Aust to return Meinhof's children to their father. The radicals, now calling themselves the Red Army Faction (RAF), return to Germany and begin robbing banks. In response, German Federal Police chief Horst Herold orders all municipal police to be put under federal command for one day. During that day, RAF member Petra Schelm is pursued by police and killed in a shootout; viewing her death as murder rather than resisting arrest, Baader and Ensslin overrule Meinhof's objections and launch a deadly bombing campaign against police stations and United States military bases. However, under Herold's command, the police respond in force to the RAF's activities and many members, including Baader, Ensslin, Meinhof, and Holger Meins, are arrested and imprisoned. They stage a hunger strike in separate prisons that results in Meins' death, while the authorities move Baader, Ensslin, Meinhof, and Jan-Carl Raspe to Stammheim Prison, where they work on their defense for their trial and smuggle orders outside. In 1975, a group of younger RAF recruits acting on these orders seize the West German embassy in Stockholm, where they kill two hostages and threaten to blow up the embassy if the prisoners are not released, but their bombs accidentally detonate, wounding everyone inside and killing RAF members Ulrich Wessel and Siegfried Hausner. The prisoners are appalled by the poor execution of their orders. Meinhof, suffering from depression and remorse over the deaths caused by the RAF's bombings, is subjected to sadistic emotional abuse by Baader and Ensslin, leading her to hang herself; the others falsely claim she was killed by the government. Upon completing her sentence in 1977, Brigitte Mohnhaupt takes over command of the RAF and organizes the assassination of Attorney General Siegfried Buback as revenge for Meins and Meinhof's "murders". Mohnhaupt, Christian Klar, and Susanne Albrecht also attempt to kidnap Dresdner Bank president Jürgen Ponto, but they kill him when he fights back. Aware the imprisoned RAF members ordered both murders, the authorities place them in solitary confinement, but Ensslin and Baader obtain radios to continue smuggling orders. Launching a new campaign of terror, Mohnhaupt abducts industrialist Hanns Martin Schleyer while the Popular Front for the Liberation of Palestine hijacks Lufthansa Flight 181, again with the goal of securing the prisoners' release, but the West German government refuses to negotiate for Schleyer, while the PFLP hijackers are defeated by GSG 9. Baader and Ensslin tauntingly warn a negotiator and a prison chaplain respectively that the violence will continue; however, the latter also confides that she fears she will be killed soon. The next morning, Baader and Raspe are found dead from gunshot wounds next to smuggled handguns, while Ensslin is found having been hung from her cell's barred window; Irmgard Möller is also found stabbed four times in the chest, but she survives. The news devastates the RAF, who insist they were murdered, but Mohnhaupt explains that they, like Meinhof, were "in control of the outcome until the very end". The RAF then murders Schleyer, signifying the continuation of RAF terrorism past the original members.

Congressman Phil Hammersley opposes a proposed counterterrorism bill that would significantly expand surveillance powers for American intelligence agencies, arguing that it poses a threat to civil liberties. In response, National Security Agency (NSA) Assistant Director Thomas Reynolds, who supports the bill and stands to benefit professionally from its passage, orders Hammersley's assassination. His team stages the murder as a fatal car accident brought on by a heart attack. Meanwhile, labor lawyer Robert Clayton Dean is working on a case involving racketeer Paulie Pintero, leveraging a videotape — obtained through a surveillance contact known only as "Brill" — to coerce a favorable settlement. At the same time, wildlife biologist Daniel Zavitz discovers footage of Hammersley's murder captured by a remote camera; Reynolds sends his team after him. In a chance encounter, Zavitz discreetly slips the incriminating video disc into Dean's shopping bag before getting struck and killed in traffic. Reynolds' team finds Dean's business card on Zavitz's corpse and wrongly assumes that he knows about the tape. NSA agents impersonating police officers attempt to enter Dean's home without a search warrant. When Dean turns the request down, the agents later break in and plant surveillance devices in his clothes and personal effects. They also fabricate false evidence linking Dean to money laundering and an affair with Rachel Banks, Dean's ex-girlfriend and Brill's courier. As a result, Dean is fired from his law firm, has his car repossessed, his bank account frozen by the IRS, and his wife Carla, who is also a labor lawyer, kicks him out the house. Desperate, Dean calls Rachel to get in touch with Brill. The NSA intercept the call and send an impostor, but the real Brill intervenes. Brill — revealed to be Edward Lyle, a former NSA communications expert in hiding — removes the bugs on Dean's clothes and reveals the NSA's involvement. Dean starts a fire in a hotel to distract Reynolds' henchmen and is chased through a tunnel and a sewer to evade them. When Rachel is later found murdered in her apartment, Dean and Lyle locate the original disc and identify Reynolds as the mastermind. However, their hideout is raided and blown up, the disc is destroyed, and they are forced to escape. Lyle reveals his background: he once worked in Iran during the revolution and escaped after his partner, Rachel's father, was killed. He now lives off the grid. While Lyle urges Dean to disappear, Dean insists on exposing Reynolds. They record Congressman Sam Albert, a supporter of the surveillance bill, in a compromising situation, then manipulate Reynolds into believing he is being blackmailed. They lure him into a meeting under the pretense of trading the tape. At the meeting, Dean deceives Reynolds by claiming the tape is concealed at Pintero's restaurant, which is under federal surveillance. Reynolds confronts Pintero, who misinterprets the demand as a threat involving separate evidence, unfortunately, a massive shootout ensues between the gangsters and the NSA agents, leaving most of the participants dead. Lyle streams the confrontation to the FBI, prompting a raid that ends the standoff. Reynolds' involvement is exposed, the survivors are apprehended, and Dean is rescued. In the aftermath, the surveillance bill is canceled by American federal legislators, the NSA covers up Reynolds' rogue operation, and Dean is exonerated of all charges. He reunites with Carla and their son Eric. Lyle, having retreated again, sends Dean a covert farewell message via television, showing himself enjoying life in a tropical hideaway.

Former Ohio State quarterback and rookie FBI agent Johnny Utah assists senior agent Angelo Pappas in investigating a string of bank robberies by the "Ex-Presidents": robbers who wear rubber masks of former presidents Ronald Reagan, Jimmy Carter, Richard Nixon, and Lyndon B. Johnson. Rather than robbing the vault, they demand only the cash the tellers have in their drawers and are gone within ninety seconds. Pursuing Pappas's theory that the criminals are surfers, Utah infiltrates the surfing community. He fabricates a family tragedy to persuade orphaned surfer and restaurant waitress Tyler to teach him to surf after she saves him from drowning during his first attempt. Through her, he meets Bodhi, Tyler's ex-boyfriend and the leader of a gang of surfers consisting of Roach, Grommet, and Nathaniel. The group is wary of Utah, but they accept him when Bodhi recalls how a knee injury derailed Utah's football prospects. As he masters surfing, Utah finds himself drawn to the surfers' adrenaline-charged lifestyle, Bodhi's philosophies, and Tyler. Following a clue retrieved by analyzing toxins found in the hair of one of the bank robbers, Utah and Pappas lead an FBI raid on another gang of surfers, resulting in the deaths of two of them, as well as one of the agents. The raid inadvertently ruins a DEA undercover operation, as those surfers were wanted for separate charges regarding drug dealing, and they are determined not to be the Ex-Presidents. Watching Bodhi's group surfing, Utah begins to suspect that they are the Ex-Presidents, noting how close a group they are and the way one of them moons other surfers in the same manner one of the robbers does. Utah and Pappas stake out a bank, and the Ex-Presidents appear. While wearing a Reagan mask, Bodhi leads Utah on a foot chase through the neighborhood, which ends when Utah's old injury flares up after he jumps into a flood control channel. Despite having a clear shot, the injured Utah allows Bodhi to escape. At a campfire that night, it is confirmed that Bodhi and his gang are the Ex-Presidents. Tyler discovers Utah's FBI badge and angrily terminates their relationship. Shortly afterward, Bodhi coerces Utah into skydiving with the group. After the jump, Bodhi reveals that he knows Utah is an FBI agent and has arranged for his friend Rosie, a non-surfing thug, to hold Tyler hostage to blackmail him into assisting the Ex-Presidents with their last bank robbery of the summer. During the robbery, they decide to infiltrate the vault, causing them to take longer than normal. Grommet is killed when an off-duty police officer and one of the bank security guards attempt to foil the robbery. The robbers kill the officer and security guard, then abandon Utah. Utah is arrested for the robbery and castigated by FBI director Ben Harp for the murders, but Pappas punches Harp out after an angry altercation and vows to bring in Bodhi himself. Pappas and Utah head to the airport where Bodhi, Roach, and Nathaniel are about to leave for Mexico. During a shootout, Pappas and Nathaniel are killed, and Roach is seriously wounded. With Roach aboard, Bodhi forces Utah onto the plane at gunpoint. Once airborne and over their intended drop zone, Bodhi and Roach put on their parachutes and jump from the plane, leaving Utah to take the blame. With no other parachutes available, Utah jumps from the plane with Bodhi's gun and intercepts him in mid-air. Despite landing safely, Utah's knee gives out again, allowing Bodhi to escape. Bodhi meets with Rosie, who frees Tyler; with Roach dead from his wounds, the two men flee the country and go their separate ways. Nine months later, Utah tracks Bodhi to Bells Beach in Victoria, Australia, where a record-breaking storm is producing lethal waves. This is an event Bodhi had talked about experiencing, calling it the "50-year storm." Bodhi begs Utah to release him so he can ride the once-in-a-lifetime wave, and Utah, knowing Bodhi will not come back alive, agrees and bids him farewell. As Bodhi surfs to his death, Utah walks away, throwing his FBI badge into the ocean.

In 2007, " environmentalist " Lucy Mirando becomes CEO of the Mirando Corporation, succeeding her twin sister Nancy. Announcing they have been breeding a special kind of "super pig", 26 specimens are sent to farmers around the world. In about 10 years from now, one will be crowned the winner as the best super pig. In 2017, a teenage girl named Mija lives in the South Korean mountains with her grandfather and their super pig Okja. Mija and Okja have a very close relationship as they spend much of their time together. At one point, Okja saves Mija from falling off a cliff. They are visited by Mirando spokesperson and zoologist Dr. Johnny Wilcox, who declares Okja the best super pig, and announces that they will take her to New York City. Her grandfather gives Mija a solid gold pig figurine, explaining he saved up to replace Okja when she was taken away. Devastated, Mija goes to Seoul to find Okja, where she sees her being loaded onto a truck. Mija chases down the truck, but it is intercepted by the Animal Liberation Front. In the resulting chaos, Mija and Okja run away and are eventually saved by the ALF led by Jay. The truck driver Kim Woo-shik resigns from his job. Jay asks another ALF member K to translate and tell Mija that they plan to put a recording device in Okja's ear and let her be recaptured by the Mirando Corporation to document how they mistreat animals. Mija asks them to return her to the mountains, but K purposely mistranslates and tells them Mija agrees. They leave and Okja is recaptured. To minimize PR damage to the company, Lucy pays for Mija to come to New York to stage a heart-warming reunion with her pig. Okja is taken to a laboratory where she is forcibly bred with another super pig and flesh is taken from her for a taste test. After the ALF sees the footage, K reveals that he lied to the rest of the group about Mija's support of the plan. Jay beats up K and expels him from the ALF while promising to return his equipment when they are done with it. In New York, Mija has to comply with the Mirando Corp. Jay slips into her room and tells her they plan to rescue Okja while on stage. During the Mirando parade, a battered and temporarily blinded Okja attacks Mija. Jay tries to hurt Okja to protect the girl, but Mija doesn't let him and calms Okja down. The ALF shows Okja's mistreatment to the public, who quickly turn against Mirando. Lucy surrenders Mirando back to Nancy who contacts the private security firm Black Chalk to take out the ALF members. Okja is recaptured and the ALF members are arrested except for Mija and Jay who are rescued by a remorseful K. Nancy starts full production at the slaughterhouse. K, Mija, and Jay travel to a processing plant in search of Okja and find her being forced up a ramp into a slaughterhouse. On the verge of being slaughtered, Mija shows a Mirando employee a photo of herself with baby Okja, prompting him to stop. Nancy arrives and Mija offers the gold pig in exchange for Okja's life. Although initially reluctant, Nancy agrees as she deemed it a good business deal, having Jay and K arrested by Black Chalk. As Mija and Okja are escorted away, a pair of super pigs push their newborn through the electric fence to Okja to hide and rescue from the farm. Back in the countryside, Mija resumes her life with her grandfather, Okja, and the new piglet. She then joins her grandfather for dinner as Okja looks on. In a post-credits scene, Jay is released from prison, boarding a bus with K and the other released members of the ALF. With their newest member Kim Woo-shik, who was revealed to have started mirandoisfucked.com, they plan to disrupt a major Mirando shareholders meeting as more new recruits are revealed.

In 2293, the Federation starship Excelsior, commanded by Captain Hikaru Sulu, discovers that the Klingon moon of Praxis has been destroyed in a mining accident. The loss of Praxis and the ecological devastation of the Klingon homeworld throws the Klingon Empire into turmoil. No longer able to afford war with the Federation, the Klingons pursue peace. Starfleet sends the Federation starship Enterprise to meet with the Klingon Chancellor Gorkon and escort him to negotiations on Earth. Enterprise Captain James T. Kirk, whose son David was murdered by Klingons, opposes peace and resents the assignment. Enterprise and Gorkon's battlecruiser rendezvous and continue towards Earth, with the two command crews sharing a tense meal. Later that night, Enterprise appears to fire torpedoes at the Klingon ship, disabling its artificial gravity. During the confusion, two men wearing Starfleet spacesuits and magnetic boots beam aboard the Klingon vessel, kill two crew members, and mortally wound Gorkon before escaping. Kirk surrenders to avoid armed conflict and beams aboard with Doctor Leonard McCoy to try and save Gorkon's life. The chancellor dies, and Gorkon's chief of staff, General Chang, arrests Kirk and McCoy for his assassination. A Klingon court finds the pair guilty and sentences them to life imprisonment on the frozen planetoid Rura Penthe. Gorkon's daughter Azetbur becomes the new chancellor and continues diplomatic negotiations; the conference is relocated for security, and the new location is kept secret. While several senior Starfleet officers want to rescue Kirk and McCoy, the Federation president refuses to risk full-scale war; Azetbur likewise refuses to invade Federation space. Kirk and McCoy arrive at the Rura Penthe mines and are befriended by Martia, a shapeshifter, who offers them an escape route; in reality, it is a ruse to make their arranged deaths appear accidental. Once her betrayal is revealed, Martia transforms into Kirk's double and fights him, but is killed by the prison governor to silence any witnesses. Kirk and McCoy are beamed aboard Enterprise by Spock, who has assumed command and launched an investigation in Kirk's absence. Determining that Enterprise did not fire the torpedoes, the crew searches for the assassins. Kirk and Spock set a trap to draw out the accomplice in sick bay and discover that the killer is Spock's protégé, Valeris. To find the identity of the other conspirators, Spock initiates a forced mind-meld and learns that Federation, Klingon, and Romulan officials conspired to sabotage the peace talks. The torpedoes that struck Gorkon's cruiser came from Chang's ship, which has the unique ability to fire its weapons while cloaked. Enterprise and Excelsior race to Khitomer, the location of the peace talks. Chang's cloaked ship attacks and inflicts heavy damage on Enterprise. At the suggestion of Spock and Uhura, Spock and McCoy modify a torpedo to home in on the exhaust emissions of Chang's ship. The torpedo impact reveals Chang's location, and Enterprise and Excelsior destroy his ship with a volley of torpedoes. The crews from both ships beam to the conference and thwart the assassination attempt on the Federation president's life. Starfleet Command orders Enterprise to return to Earth to be decommissioned. Kirk decides to take his ship on one last cruise instead, and notes in his log a new generation of explorers will continue their legacy.

In the first years of the 21st century a third World War broke out. Those of us who survived knew mankind could never survive a fourth; that our own volatile natures could simply no longer be risked. So we have created a new arm of the law – The Grammaton Cleric, whose sole task is to seek out and eradicate the true source of man's inhumanity to man; his ability to feel. Established by survivors of World War III, the totalitarian city-state of Libria blames human emotion as the root of all conflicts. It strictly outlaws all activities or objects that stimulate emotion, with violators labeled Sense Offenders and sentenced to death. The population has to take a daily injection of the emotion-suppressing drug called Prozium II. Libria is governed by the Tetragrammaton Council, led by "Father", who communicates propaganda through giant video screens. The police force is led by the Grammaton Clerics, elite fighters trained in the art of gun kata. Clerics frequently raid homes to search for and destroy illegal materials – art, literature and music – executing violators on the spot. A resistance movement, known as the "Underground", emerges to topple Father and the Tetragrammaton Council. In 2072, John Preston is a high-ranking Cleric whose wife, Viviana, was executed as a Sense Offender, leaving him as a single parent of two. Following a raid, Preston's partner Errol Partridge saves a book of poems by W. B. Yeats instead of turning it in for incineration. He follows Partridge to the Nether – a term for regions outside the city – and finds him reading the book. Seeing Preston, Partridge claims he gladly pays the price of feeling emotion. Preston executes Partridge. Preston accidentally breaks his last vial of Prozium and is unable to refill them before the next raid. Brief episodes of emotion set in evoking memories, stirring feelings, and making him more aware of his surroundings. He intentionally skips additional doses of Prozium, hiding them behind his bathroom mirror. Partridge is replaced with an ambitious, career-conscious Brandt, who admires Preston's work as a Cleric. On a raid, they arrest Sense Offender Mary O'Brien. Preston prevents Brandt from executing O'Brien, saying she should be interrogated. Preston feels remorse for killing Partridge, develops an emotional relationship with O'Brien, and seeks atonement. He uncovers clues that lead to meeting Jurgen, the Underground leader. Jurgen plans to disrupt Prozium production to spark an uprising and convinces Preston that Father must be assassinated. Vice-Counsel DuPont meets with Preston to reveal that there is a traitor in the upper ranks of the Clerics, and assigns Preston the task of unmasking the traitor. Relieved, Preston accepts and promises to locate the Underground's leadership. When O'Brien is set to be executed, Preston attempts to stop the execution and fails. His memory of his wife's execution triggers an emotional breakdown. Brandt, who has been suspecting Preston of being a Sense Offender, arrests and brings him before DuPont. Preston tricks DuPont into believing that Brandt is the traitor. Preston is told that his home will be searched as a formality. He rushes home to destroy the hidden vials only to discover his son, who stopped taking Prozium after his mother died, already has. Jurgen tells Preston to capture the resistance leaders to regain Father's trust, hoping it will get him close enough to assassinate Father. Preston is granted an exclusive audience with Father only to discover that Brandt was not arrested; it was part of a ruse to capture Preston and the Underground. DuPont reveals he is Father, having secretly replaced the original Father who died, and that his cabal doesn't take Prozium to suppress emotion. He taunts Preston, asking how it felt to betray the Underground. Having anticipated the trap, Preston fights his way through an army of bodyguards to DuPont's office, confronting and killing Brandt in a katana battle. DuPont and Preston engage in a gun kata showdown. Preston wins as DuPont pleads for his life, asking "Is it really worth the price?" Paying homage to Partridge's last words, he responds "I pay it gladly" and kills DuPont to satiate his need for revenge. He destroys the command center that broadcasts Father propaganda. Preston watches with satisfaction from above as the Underground destroys Prozium manufacturing plants, signaling the beginning of the revolution.

Growing up in Texas, Chris Kyle is taught by his father how to shoot a rifle and hunt deer. Years later, Chris has become a ranch hand and rodeo cowboy, and returns home early to find his girlfriend in bed with another man. After telling her to leave, he sees news coverage of the 1998 U.S. embassy bombings and decides to enlist in the Navy. He qualifies for special training and becomes a sniper with the U.S. Navy SEALs. Chris meets Taya Studebaker at an Irish pub in San Diego, and the two soon marry. He is sent to the Iraq War after the September 11 attacks. His first kills are a woman and a boy who attacked U.S. Marines on patrol with a Russian-made RKG-3 anti-tank grenade. Chris is visibly upset by the experience, but later earns the nickname "Legend" for his many kills. Assigned to hunt for the al-Qaeda leader, Abu Musab al-Zarqawi, Chris interrogates a family whose father offers to lead the SEALs to "The Butcher", al-Zarqawi's second-in-command. The plan goes awry when The Butcher captures the father and his son, killing them while a sniper pins down Chris. This sniper goes by the name Mustafa and is an Olympic Games medalist from Syria. Meanwhile, the insurgents issue a bounty on Chris. Chris returns home to his wife and the birth of his son. He is distracted by memories of his war experiences and by Taya's concern for them as a couple. She wishes he would focus on his home and family. Chris leaves for a second tour and is promoted to chief petty officer. Involved in a shootout with The Butcher, he helps kill him. Chris becomes increasingly distant from his family when he returns home to a newborn daughter. On Chris's third tour, Mustafa seriously injures a unit member, Ryan "Biggles" Job, and the unit is evacuated back to base. When they decide to return to the field and continue the mission, another SEAL, Marc Lee, is killed by gunfire. Guilt compels Chris to undertake a fourth tour, and Taya tells him she may not be there when he returns. Back in Iraq, Chris is shocked to learn Biggles died in surgery to repair the wounds he sustained. Assigned to kill Mustafa, who has been sniping U.S. Army combat engineers building a barricade, Chris's sniper team is placed on a rooftop inside enemy territory. Chris spots Mustafa and takes him out with a risky long-distance shot at 2,100 yards (1,920 m), but this exposes his team's position to numerous armed insurgents. Amid the gunfight and low on ammunition, Chris tearfully calls Taya and tells her he is ready to come home. A sandstorm provides concealment for a chaotic escape in which he is injured and almost left behind. After Chris gets back stateside, on edge and unable to adjust fully to civilian life, a Veterans Affairs psychiatrist asks if he is haunted by all the things he did in war. When he replies that "all the guys couldn't save" haunt him, the psychiatrist encourages him to help severely wounded veterans in the VA hospital. After that, Chris gradually begins to adjust to home life. Years later, on February 2, 2013, Chris says goodbye to his wife and family as he leaves in good spirits to spend time with Eddie Ray Routh, a veteran suffering from PTSD, at a shooting range. An on-screen subtitle reveals that Chris was killed that day by Routh, followed by archive footage of crowds standing along the highway for his funeral procession. More are shown attending his memorial service.

British Army Colonel Katherine Powell discovers an undercover British/Kenyan agent has been murdered by the Al-Shabaab group. From Northwood Headquarters, she takes command of a mission to capture three of the ten highest-level Al-Shabaab leaders meeting in a safe house in Nairobi. A multinational team works on the capture mission, linked by video and voice systems. Aerial surveillance is provided by a USAF MQ-9 Reaper drone controlled from Creech Air Force Base in Nevada by Second Lieutenant Steve Watts. Undercover Kenyan field agents, including Jama Farah, use short-range ornithopter and insectothopter cameras to link in ground intelligence. Kenyan special forces are positioned nearby to make the arrest. Facial recognition to identify human targets is done at Joint Intelligence Center Pacific at Pearl Harbor. The mission is supervised in the United Kingdom by a COBRA meeting that includes British Lieutenant General Frank Benson, two government ministers and a ministerial under-secretary. Farah discovers three high-level targets arming two suicide bombers for a presumed attack on a civilian target, prompting Powell to change the mission objective from "capture" to "kill". She requests Watts prepare a precision Hellfire missile attack on the building and solicits the opinion of her British Army legal counsel who advises her to seek approval from superiors. Frustrated, Benson asks permission from the COBRA members, who can't find consensus and refer the question to the UK Foreign Secretary who is on a trade mission to Singapore. He in turn defers to the United States Secretary of State, who declares the American suicide bomber an enemy of the state. The Foreign Secretary then insists that COBRA take due diligence to minimise collateral damage. Alia, who lives next door, is near the target building selling her mother's bread. The senior military personnel stress the risk of letting would-be suicide bombers leave the house. The lawyers and politicians involved in the chain of command argue the personal, political, and legal merits around launching a Hellfire missile attack in a friendly country not at war with the US or UK, with the significant risk of collateral damage. Watts sees a more direct risk of little Alia selling bread outside the targeted building, and they delay firing until she moves. Farah is directed to buy all of Alia's bread so she will leave, but doing so blows his cover, and he flees without collecting it. Seeking authorisation to execute the strike, Powell orders her risk-assessment officer to find parameters that will let him quote a lower 45% risk of civilian deaths. He re-evaluates the strike point and assesses the probability of Alia's death at 45–65%. She makes him confirm only the lower figure which she reports up the chain of command. The strike is authorised, and Watts fires. The missile destroys the building and injures Alia, but one conspirator survives. Watts is ordered to fire a second missile, which strikes the site just as Alia's parents reach her. They rush Alia to a hospital, where she is pronounced dead. In the London situation room, the under-secretary berates Benson for killing from the safety of his chair. Benson counters that he has been on the ground in the aftermath of five suicide bombings and adds as he is leaving, provoking her to tears: "Never tell a soldier that he does not know the cost of war."

In the future, Earth is governed by the United Citizen Federation, a stratocratic regime founded generations earlier by "veterans" after democracy and social scientists brought civilization to the brink of ruin. Citizenship is exclusively earned through federal service, which grants rights—like voting and procreation—that are withheld from ordinary civilians. Humans, who are now capable of interstellar travel, conduct colonization missions throughout the galaxy, bringing them into conflict with a race of highly evolved insectoid creatures dubbed "Arachnids" or, derisively, "bugs". Against his parents' objections, teenage jock Johnny Rico enlists in the Mobile Infantry to remain close to his girlfriend, spaceship pilot Carmen Ibanez. Their psychic friend Carl Jenkins joins military intelligence, while Isabelle "Dizzy" Flores—who is in love with Rico—deliberately transfers to his squad. Carmen ends her relationship with Rico due to their diverging career paths and her growing feelings for a fellow pilot, Zander Barcalow. During training, Rico impresses his drill sergeant, Zim, earning a promotion to squad leader. However, Rico makes a mistake during a training exercise, which leads to the death of a squad member and the resignation of another, resulting in Rico's demotion and flogging. Disheartened, Rico quits, but re-enlists after learning that an asteroid sent by the Arachnids has destroyed Buenos Aires, killing millions, including his parents. An invasion force is deployed to Klendathu, the Arachnids' home planet, but military intelligence underestimates the Arachnids' defensive abilities, leading to hundreds of thousands of human casualties. Badly wounded, Rico is rescued by Lieutenant Jean Rasczak, his former high school teacher, but is mistakenly reported dead, devastating Carmen. Following his recovery, Rico, Dizzy, and squadmate Ace Levy join Rasczak's elite unit, the Roughnecks. After Rico defeats a gigantic "Tanker Bug" on the disputed planet of Tango Urilla, he is elevated to the rank of corporal for his valor and begins a romantic relationship with Dizzy. Responding to a distress signal on the Arachnid-controlled Planet P, the Roughnecks discover an Arachnid-ravaged outpost and are ambushed by the bugs. Carmen and Zander recover the surviving Roughnecks by dropship, but not before Dizzy is fatally impaled by an Arachnid and Rico mercy kills the mutilated Rasczak. The group returns to the fleet assembled in orbit above P, where Dizzy is eulogized. Jenkins, now a colonel, reveals the Roughnecks were deliberately ordered into the trap, justifying it as a necessary sacrifice to confirm the existence of a "Brain Bug", an intelligent Arachnid strategically directing the others. He assigns Rico command of the Roughnecks and field-promotes him to lieutenant, instructing him to return to P and capture the Brain Bug. As the battle commences, Carmen's ship is destroyed by the Arachnids; she and Zander escape in an escape pod, but it crashes into an underground tunnel system. The pair are captured by the Arachnids, and the Brain Bug consumes Zander's brain, killing him and absorbing his knowledge. Rico directs his squad to complete their mission while he, Ace, and their squadmate Watkins rescue Carmen and hold the Arachnids at bay with a miniature nuclear bomb. The Brain Bug escapes while the Arachnids attack and fatally wound Watkins, who sacrifices himself by detonating the bomb while his teammates escape. On the surface, they learn that Zim has captured the Brain Bug and the assembled troops rejoice as Jenkins psychically detects it is afraid. A propaganda broadcast details how the Brain Bug is being invasively studied to learn its secrets and ensure humanity's victory. The ad encourages viewers to enlist and do their part in the war so they can become like Carmen, now captain of her own ship, and Rico, who enthusiastically leads his troops into another battle.