The Roman Empire has been unable to fully conquer Britain, reaching a harsh stalemate in the North. The Picts engage in guerrilla warfare against the Romans along the Glenblocker forts and the Gask Ridge at the southern border of the Scottish Highlands. At the Roman outpost of Pinnata Castra, Pict warriors led by Vortix and Aeron kill the entire garrison, taking only the second-in-command, Centurion Quintus Dias, because he can speak the Pictish language. Brought before Pict king Gorlacon, who has united the northern tribes, Dias is brutally interrogated, but escapes on foot. A messenger from the fort reaches Gnaeus Julius Agricola, Roman governor of Britannia, who hopes to obtain favour with the Roman Senate and transfer back to the comforts of Rome. He dispatches the Ninth Legion under General Titus Flavius Virilus to eradicate the Pict threat, providing him with a Celtic Brigantian scout, Etain. Marching north, the legion rescues Dias from his pursuers. Etain leads them into an ambush where, surprised by flaming pitch-wood 'boulders', they are massacred and the wounded Virilus is captured. The few survivors – Dias, the legionaries Bothos, Thax, Brick, Macros and Leonidas, and the cook Tarak – set out to rescue Virilus, finding him at Gorlacon's village. Sneaking in at nightfall, they are unable to break his chains, and he orders them to return to Roman territory without him. In Gorlacon's hut, Thax suffocates the king's young son to prevent him giving them away. The next morning, Gorlacon burns his son's body on a funeral pyre and forces Virilus to fight Etain, who as a child witnessed her parents raped and slaughtered by the Romans; she kills him with a spear through the heart. Gorlacon sends her after the legionaries at the head of a group of mounted warriors, including Vortix and Aeron, to avenge his son's death. The Romans plan to travel north away from Roman territory, to throw the Picts off their trail, then head west and back south. After several days' pursuit, the Picts continually catch up with the fugitives, who jump off a cliff into a river to escape them; Tarak is killed before he can jump, and Macros and Thax become separated from the others. Dias' group camp for the night while their pursuers camp across the river. Dias and Brick raid the enemy camp, killing two men and wounding a third, who reveals they are being pursued because of the death of Gorlacon's son, which Thax had kept secret. Etain has launched her own attack on the Romans, and Dias and Brick return to discover Leonidas dead and Bothos wounded. Meanwhile, Macros and Thax have washed up further down river. The two encounter a wolf pack and end up running. When Thax falls Macros returns to help him, only for Thax to cut his Achilles tendon and leave him to the wolves. Dias, Bothos, and Brick find the forest hut of Arianne, an exiled Briton accused of witchcraft who learned Latin from a nearby Roman outpost. She gives them shelter, food, and medical attention for Bothos. When Etain and her warriors arrive, Arianne hides the Romans under her floorboards.When Bothos, Dias, and Brick leave Arianne's in the morning; Arianne, having become fond of Dias, is saddened to see him go. They find the outpost abandoned, with an order declaring that the Roman troops have retreated south by order of Emperor Hadrian. Seeing Etain's warriors approaching and tired of running, they set up a defensive position inside the fort. Brick is killed, as are Vortix, Aeron, and the rest of the Britons, with Dias finally killing Etain. Taking the Picts' horses, Dias and Bothos continue south, reuniting with Thax. Reaching Hadrian's Wall, now under construction, Thax threatens Dias, afraid he will report his dishonourable actions. They fight, with Dias choking Thax to death. Bothos, joyfully riding toward the Romans, is mistaken for a charging Pict and shot by an archer. Devastated, Dias reports to Agricola, who worries that news of the legion's annihilation will lead other tribes to revolt. Fearful of his reputation being tainted by a military failure, he decides the Ninth Legion's fate should remain a mystery and Dias must be silenced. Dias foils the attempt on his life by Agricola's daughter Drusilla. Badly wounded in the thigh, he knocks Drusilla unconscious and escapes from the camp, returning to Arianne in the forest. The film ends with Arianne kissing him after he falls from his horse.

In the near future, Michael Jennings is a reverse engineer; he analyzes his clients' competitors' technology and recreates it with improvements. To protect his clients' intellectual property and himself, Jennings undergoes memory wipes to remove knowledge of his engineering with aid of his friend Shorty. Jennings is contacted by his college roommate James Rethrick, the CEO of technology company Allcom. Rethrick offers Jennings a lengthy three-year job, during which he will be required to stay on Allcom's campus, in exchange for company stock. Jennings is hesitant but agrees. After being injected with the memory marker, Jennings is given a tour of the campus, where he meets and flirts with biologist Dr. Rachel Porter. Rethrick then introduces Jennings to his work partner, physicist William Dekker. Three years later, Jennings wakes from the memory wipe and is congratulated by Rethrick. Jennings finds that the Allcom stock he earned is valued at over US$92 million, but when he goes to see his lawyer to get the funds, he discovers that he had given all the stock away just weeks ago. Further, he is given an envelope claiming to be his possessions on entering Allcom, but it contains a random assortment of items. Confused, Jennings soon finds himself detained by the FBI. Agent Dodge accuses Jennings of having access to classified government designs that had been taken by Dekker, who is now dead. Jennings cannot answer due to the memory wipe, but finds a means to escape using the items in the envelope. As he evades the FBI, Rethrick's right-hand-man John Wolfe sees Jennings walking away and warns Rethrick they have a problem. Jennings meets with Shorty to try to figure out what happened, but then sees a lottery number result on a television, the numbers matching those on a fortune cookie message in the envelope. He realizes that he must have built a machine at Allcom to see into the future, planting items in that envelope to help fix things. At Allcom, Rethrick tries to use Jennings' machine, but instead finds that it was jury-rigged to go offline after Jennings had left. Rethrick studies Jennings' habits while at Allcom and discovers that he became romantically involved with Porter and left a secret message to meet her at a cafe later that day. Rethrick sends a body double to try to coerce Jennings to turn over the envelope, but the real Porter shows up and rescues Jennings. The two elude the FBI and Rethrick's men. While hiding, they find that the stamps on the envelopes contain microdot images taken from the device, showing newspaper headlines from the future that while Allcom became incredibly successful with the device, it led to crises on the stock markets, international political strife, a pandemic and the United States launching a pre-emptive nuclear strike. They agree that the machine must be destroyed. Using the last items in the envelope, Jennings and Porter gain access to Allcom and the machine, while separately the FBI have started to investigate Allcom. Jennings discovers the circuit he rigged and fixes it, while booby-trapping the machine to be destroyed in a few minutes. He uses the machine one last time to see himself being shot at by an FBI agent in the catwalks above the machine. Rethrick, Wolfe, and other men arrive, and Jennings and Porter escape to the catwalks. Wolfe tries to use the machine to help track Jennings, while Rethrick corners the pair on the catwalk. FBI agents storm the lab, and one appears on the catwalk, the same tableau that Jennings had seen. As the FBI fires, a watch from the envelope beeps, and Jennings dodges in time for the bullet to fatally hit Rethrick. Wolfe is killed as Jennings' booby-trap goes off and destroys the machine. After the chaos dies down and the FBI begin a full investigation, Agent Dodge finds the watch Jennings had used, but consequently hides it and declares him dead. Elsewhere, Jennings, Porter, and Shorty have moved to the countryside. Shorty was able to use his influence to rescue the cage of a pair of red-rumped parrots Porter had been raising at Allcom. Recalling the fortune cookie message from the envelope, Jennings looks in the cage and finds a lottery ticket for the winning jackpot of US$90 million.

In December 1999, insurance investigator Virginia "Gin" Baker assesses the theft of a valuable Rembrandt painting from a New York City penthouse. Gin informs her boss, Hector Cruz, that she suspects the involvement of world-class international thief Robert "Mac" MacDougal, an elderly man who steals for the challenge. Cruz assigns her to investigate. In London, Mac quickly realizes that Gin is following him and confronts her. She claims to be a thief in need of Mac's help to steal a valuable Chinese mask from the highly-secure Bedford Palace. After Gin passes his test by obtaining the Palace floorplans, Mac brings her to his isolated Scottish castle to prepare. There, Gin confesses to stealing the Rembrandt, prompting Mac to reveal that he, in turn, intercepted it before it reached her client. The pair train for the heist, clashing over Mac's over-preparedness and resisting their mutual attraction. Later, unaware that Mac is listening in, Gin contacts Cruz to explain her plan to entrap Mac. That night, Mac and Gin break into Bedford Palace and steal the mask. Before they can escape, however, Mac threatens to drown Gin if she does not admit she is trying to arrest him. Gin claims that her insurance job is a cover identity, and she has no intention of arresting him as she needs him for another heist. In Kuala Lumpur, Gin reveals her plan to infiltrate the Malaysian branch of the International Clearance Bank (ICB) housed in the Petronas Towers. At midnight on New Year's Eve, the bank's global computer system will briefly shut down for thirty seconds to verify its integrity due to the millennium bug. During this window, Gin and Mac plan to use her custom software to siphon small amounts from thousands of corporate transactions into her account. Concerned for Gin's safety, Mac attempts to cancel the heist, but his contact, Aaron Thibadeaux, coerces him to proceed and provides Cruz with photos of Mac and Gin in an intimate moment. Cruz confronts Gin for answers, but she convinces him that it is part of her strategy to incriminate Mac. As the Millennium celebrations commence on New Year's Eve, Cruz oversees increased security forces in the Petronas Towers. Gin and Mac hack the surveillance system to conceal their presence and break into the vault housing the ICB system. At the stroke of midnight, Gin's software successfully transfers just over $8 billion to her account, but alarms are triggered when she disconnects her laptop. She and Mac evade the pursuing forces and climb to the interlinked second tower across cables of suspended lights, but when the cable snaps, Gin loses her miniature parachute. The pair reach a large ventilation shaft and Mac forces a tearful Gin to escape with his parachute while he remains behind, promising to meet her at Pudu train station. The following morning, Mac meets Gin at the station, accompanied by Thibadeaux, who reveals himself as a Federal Bureau of Investigation (FBI) agent. Mac confesses that he was arrested two years earlier and given a deal to avoid jail by entrapping Gin, who has long been under FBI suspicion. As a train arrives at the station, Mac reveals that he has fallen in love with Gin, and that he only surrendered $7 billion to the FBI, before slipping her a gun and documents to escape the country. Gin feigns holding Mac at gunpoint and escapes on the train, pursued by the FBI. As Mac sits at the station alone, Gin reappears, having jumped trains mid-station. Happily reunited, Gin proposes their next heist.

At the close of the Iraq War, U.S. Army Staff Sergeant Shane Matthews, a sniper, along with his spotter, Sergeant Allen Isaac, are sent to investigate a pipeline construction site in the Iraqi desert where contractors and their security detail have all fallen victim to a sniper. The pair patiently wait 22 hours on overwatch before determining that the site is clear. Matthews proceeds to investigate the site, but is shot by a famed Iraqi sniper nicknamed "Juba". Isaac tries to rescue the dying Matthews, but he is also wounded in the right knee and has his radio damaged and his water bottle destroyed in the process. Alone, Isaac takes cover behind an unsteady wall and tends to his wounds. The sniper has a radio tuned into the American channel, and uses it to communicate with Isaac initially under the pretense of being a high ranking allied soldier at another site. The deception allows the sniper to get other useful information from Isaac. Throughout their various one-sided attempts at conversation, we learn that the sniper does not claim to be the mythical Juba mentioned earlier in the film, a nom de guerre for various Iraqi Insurgent snipers notorious for filming their attacks on American soldiers. Matthews regains consciousness and subtly gets Isaac's attention that he is still alive. Matthews slowly crawls towards his rifle in the midst of the dusty wind while Isaac distracts Juba with small talk. Matthews believes that the sniper is hiding at the top of some rubble nearby and fires in that direction. The dusty wind settles quickly. The sniper sees Matthews and fires, injuring Matthews in the left shoulder as he crawled towards the wall, and kills him with a second shot. Isaac's attempts to call headquarters for help are stymied by the loss of his radio antenna. He attempts to repair this with one from a dead contractor's radio, only to discern that the sniper had used the earlier response team as a ruse to call for help and lure another response force into his jaws. Isaac hears the rescue helicopters coming, so he pushes down the wall and uses Matthews' rifle to try to kill Juba, or at least flush him out so the rescue chopper can see the trap. Juba fires at Isaac twice and misses. Isaac now has the sniper's location and fires his only round. Isaac stands up and waits for Juba's next shot, but it never comes. Thus he assumes his shot was successful, and Juba is either injured or dead. The helicopters then land and the rescue team picks up Isaac and Matthews. Once the helicopters take off, Juba shoots down both in rapid succession. He is then heard over the radio, calling for another rescue to set a new trap.

After the September 11 attacks, Jack Ryan, studying at the London School of Economics, becomes a U.S. Marine officer serving in Afghanistan, until his spine is critically injured while saving two of his fellow Marines when his helicopter is shot down. During a lengthy recovery back in the United States, he meets Cathy Muller, a medical student helping him to recover. Later, Thomas Harper, a veteran CIA official, recruits Jack. Ten years later, Ryan is working on Wall Street covertly for the CIA looking for suspicious financial transactions that indicate terrorist activity, while Muller is now his fiancée. When Russia loses a key vote before the United Nations and the markets do not respond as expected, Ryan discovers that billions of dollars possessed by Russian business interests, most of which belong directly or indirectly to Russian oligarch Viktor Cherevin, have disappeared. Ryan's employer conducts business with one of Cherevin's businesses. When Ryan finds certain accounts inaccessible to him as an auditor, he uses it as a legitimate excuse to visit Moscow and investigate. After narrowly surviving an attempt on his life by an assassin posing as his bodyguard, Ryan contacts the CIA and is surprised that his backup is Harper. During their debrief at Staraya Square, Ryan explains how Cherevin's web of international investments makes the United States vulnerable to complete financial collapse following a staged terrorist attack. The next day, Ryan is met by Katya, who escorts him to Cherevin's office. At their meeting, he is told that the problem company and all its assets have just been sold, preventing an audit. Meanwhile, Muller suspects that Ryan is having an affair and flies to Moscow. Against protocol for unmarried couples, Ryan reveals his CIA employment to her. Improvising the situation, Harper convinces Muller to help them infiltrate Cherevin's offices. Ryan and Muller meet Cherevin at an upscale restaurant across the street from the office. Ryan, who supposedly had too much to drink already before dinner, acts boorish and Muller suggests he "take a walk." Having obtained Cherevin's access card, Ryan enters an office adjacent to Cherevin's, where he downloads crucial files from the computer, while Muller remains with Cherevin distracting him with a variety of topics, including his terminal cirrhosis symptoms. The suspicious computer activity is detected, and guards rush through the building to locate the intruder. Katya is alerted to find Cherevin, who in a rage takes Muller out of the restaurant to return to his office. On the street, they run into Ryan, who apologizes for his behavior and leaves with Muller. Cheverin's men locate and invade the CIA group's base and kidnap Muller; enraged, Ryan follows and rescues her. Ryan and the CIA discover Cherevin has secretly propped up the struggling Chinese and Japanese state economies for years, leaving the U.S. economy vulnerable, as well as using a falsified death certificate to place his son, Aleksandr, in the U.S. as a sleeper agent. Ryan uses his talent for pattern recognition to determine that Aleksandr will execute a terrorist attack on Wall Street. Returning to New York City, he locates and catches up to a fake police response vehicle driven by Aleksandr, and discovers a bomb inside the vehicle. Unable to defuse it, he hijacks the vehicle and crashes it into the East River while jumping out; the bomb detonates, killing Aleksandr. Cherevin's fellow conspirators kill him to cover their tracks. Afterward, Ryan, now married, and Harper are called to the White House to brief the President on their next move.

A scientist in the distant future has set out to avert a catastrophic ecological disaster and sends a small number of high tech devices that resemble toys back in time to the 21st century. Ending up in Seattle, they are discovered by siblings Noah Wilder and his younger sister Emma. The "toys" are initially incomprehensible to them, other than one which appears to be a stuffed rabbit. The children keep their discovery a secret from their parents. Emma becomes telepathically connected to the rabbit, naming it "Mimzy", which imparts knowledge onto her. The children gain genius -level intellects and psionic powers – Noah can teleport objects using a card-sized rectangle of green lines of light and a conch shell to control spiders, but thanks to her link, Emma develops more advanced abilities, becoming the only one who can use the "spinners", stones that can float and produce a force field. Emma describes herself as "the chosen one" but names Noah as "the engineer" without which she cannot "build the bridge to the future". The children's parents and Larry White, Noah's science teacher, discover the devices and the children's powers. By mistake, Noah causes a power outage over half the state of Washington, alerting the FBI to their activities. The family is held for questioning by Agent Nathaniel Broadman, during which Mimzy is revealed as artificial life using nanotechnology created by Intel. Emma relates a dire message from Mimzy which states that many of her kind were sent into the past before, but none of them were able to return to their proper time period, because they lacked an "engineer" like Noah, and now Mimzy, the last one that the scientist was able to send back, is beginning to deteriorate. To save the future, Mimzy must acquire a sample of uncorrupted human DNA to correct the damage done to DNA by ecological catastrophes. The FBI do not believe them, so Noah and Emma use their powers to escape. Mimzy absorbs a tear from Emma, which contains her DNA. Via the time portal that Noah constructs using the toys, Mimzy returns to the future, leaving a Sri Yantra symbol; Larry, who witnessed the event, says he saw "numbers", a reference to a dream he had that related to him winning lottery numbers he had missed out before by never buying a ticket. In the future, Mimzy provides the genetic information required to restore humanity, both physically and mentally, with Emma coming to be dubbed "Our Mother" by the populace.

In Los Angeles, a man known as Mr. Jigsaw murders Billie York because she possesses a microfilm containing a recipe that can turn cocaine into cookies. Her former partner, Wes Luger, who is about to retire, is assigned the case by the reluctant captain Doyle, who dismisses it as a suicide but gives Luger the case. The catch is that Luger will have to be partnered with Jack Colt, a burned out cop who recently lost his dog, Claire. The two visit Harold Leacher, who tells them that Colt's former general in the Vietnam War, Mortars, is heading the operation. Meanwhile, Jigsaw and Mortars visit Mike McCraken, whom Jigsaw murders for losing the microfilm. After finding the body, Colt and Luger go to Rick Becker, who claims that he laundered money with York (the money actually being in the laundry machine), but Rick is shot multiple times by unknown assailants, forcing Colt and Luger to go to the Wilderness Girls factory. The head, Destiny Demeanor, claims no knowledge of the operation during questioning, but she is revealed to be working for Mortars and his gang. Colt meets Luger's family, but he runs away when they try to seduce him. Destiny and Colt hang out at Colt's house, while Mortars sends a helicopter to destroy Colt's house (a trailer that is actually a mansion inside), but they accidentally destroy John McClane 's house. Due to lack of evidence, Doyle dismisses the case, but Colt still decides to stop the operation, much to the dismay of Luger. Luger is a by-the-book cop, after he took an unscheduled break from his crossing guard duties (as a child), which led to an old lady being run over by a car and killed. Colt breaks in and Destiny, now having fallen in love with Colt, attempts to stop Mortars, but Mortars shows that he was the one who kidnapped Claire, revealing Rick and Claire chained to a wall (Rick actually having survived the incident). Mortars shoots Destiny, who clings to life long enough to confess her feelings for Colt. Colt manages to catch up with Mortars, but then Luger shows up, having considered what Colt said to him earlier. He shoots and kills Mortars, and Colt kills Jigsaw, but starts a fire that destroys the whole factory. Doyle shows up, and asks Luger to stay in the force. Luger agrees, but as long as Colt is his partner. In the end, Destiny, having survived, shows up with Rick and Claire, and the team dances to " Bohemian Rhapsody ".

In 1957, Soviet agents led by Colonel Doctor Irina Spalko kidnap American archeologist Indiana Jones and his partner George "Mac" McHale. They infiltrate Hangar 51 in Nevada and use Jones to locate a mummified alien from the Roswell incident. Jones locates the mummy before being double-crossed by Mac, but escapes to a nearby model town at the Nevada Test Site, minutes before an atomic bomb test. He survives the blast in a lead-lined refrigerator in one of the town's mock houses before being rescued and interrogated by the FBI. Returning to Marshall College, Jones discovers he has been placed on an indefinite leave of absence. Mutt Williams, a young greaser, approaches Jones and informs him that his former colleague, Harold "Ox" Oxley, found a crystal skull in Peru in search of the mythical city Akator. KGB agents attempt to capture them, but the two escape, during which they instigate a brawl between the greasers and jocks and lose them during the chase through the College Campus District. The duo later travels to Peru. In Peru, they find carvings made by Ox, which lead the pair to the grave of Francisco de Orellana, which contains an elongated crystal skull. Leaving the grave, they are captured by the Soviets and taken to a camp in the Amazon rainforest. They are reunited with Mac, Spalko, an addled Ox, and Mutt's mother, Marion Ravenwood. Spalko tells Jones that the skulls are alien in origin and that she intends to use them to project Soviet propaganda into the minds of Americans. Jones has a brief telepathic connection to the skull, which commands him to return it to Akator. He realizes that Ox is attempting to communicate through automatic writing, discovering a route to the city. They first attempt an escape until Indy and Marion get caught in quicksand, during which Marion reveals that Mutt is Indy's son. Mutt manages to save them, but they are recaptured by the Soviets. While en route to Akator, Jones retakes the skull from the Soviet troops and escapes from them alongside Marion, Ox, Mutt and Mac, who claims to be a double agent, all the while leaving a trail for Spalko. Jones and his companions locate Akator, where they learn that the skull belonged to one of thirteen "interdimensional beings" whom the early Ugha tribes worshipped as deities. Spalko catches up and returns the skull to its skeleton, which comes to life and offers her the reward of omniscience. As an interdimensional portal opens above the chamber, abducting Mac and Spalko's remaining soldiers, the skeletons combine into a reanimated alien, who transfers an overwhelming amount of knowledge into Spalko's mind, vaporizing her. Jones, Ox, Marion and Mutt escape the crumbling city as a flying saucer rises from the ruins and departs for another dimension. As Ox regains his sanity, Jones and his party return to the United States, where he is reinstated at Marshall College and promoted to associate dean, and marries Marion.

A terrible storm causes hundreds of dikes to break in Zeeland, resulting in the North Sea flood of 1953. Julia, a single mother living with her parents, is caught in the middle of a catastrophic flood. She is rescued from drowning and taken to safety by her neighbor Aldo, who is a member of the armed forces. However, her baby is left in a wooden box in the attic of Julia's parental home. Together Julia and Aldo return to the disaster area to look for the baby. When they finally find the box, it is empty, and they conclude that someone must have taken the child. The child ended up with a woman who recently lost her own baby in a car accident. Julia met her but because the woman did not want to lose the baby, she hid him from Julia. Eighteen years later, Julia meets her son and the woman again and she finds out what has happened.

Hopper, an archaeology professor, is exploring a remote cave system on the trail of missing hippies from the 1970s. After discovering what appears to be a cowboy paused in place in a tunnel, he returns to town and dismisses his graduate students, Taylor and Jackie, stating that their research is done. Several days later, as Hopper has not returned, Taylor and Jackie go looking for him, with their friend Cara, who brings her sister, Veeves, and her friend Furby. Following Hopper's trail to the campsite by a cave, they find an entrance with climbing ropes leading inside. They decide to follow it, but Furby chooses to stay behind as backup for the base camp. They lower themselves into the cave, hearing strange noises. When Furby does not answer their radio calls, Jackie tries to climb back out, but the rope frays, and she falls, injuring herself and Taylor. Calling for help, they receive a transmission from inside the cave and follow it. At a different junction, they discover another opening to the cave and Furby, dead with a broken neck. Watching his video recordings, they notice several days elapsed from his perspective, while only an hour had passed in the cave. He began researching the hippies' belongings, discovering they were Hopper's parents and that they were accompanied by his sister. His parents were following legends of the Fountain of Youth and speculated that this cave system was the root of the story. Furby found another cave opening. After several days, he went into the cave to retrieve keys for a vehicle but fell when his rope severed. Taylor deduces the cave is inside a time distortion where events move more slowly. With few options, Cara free-climbs out of the cave to get a GPS signal. Outside, the terrain has become barren, and there is no signal. Returning to the cave, comparing video recordings, Cara has experienced about thirty minutes on the surface while she had been gone at most a few seconds from the others' viewpoint, confirming Taylor's theory. Reviewing Furby's footage again, they learn that he survived the fall but was murdered by a caveman. Cara and Taylor deduce the time difference is much more drastic than they suspected and entire years are passing within seconds, meaning the few hours they have been in the cave is enough to span several thousand years outside. Hearing more howling, Cara prepares to climb out again for help but is interrupted by a futuristic 8-foot-tall humanoid spaceman descending via a retractable ladder. A caveman suddenly attacks, but is subdued non-lethally. They flee just to find a whole tribe of cavemen inspecting the dead bodies of the cowboy and Hopper's parents. Discovered, Taylor fights the cavemen and is killed. The spaceman returns, protects the others from the cavemen, and then places Taylor into a healing pool of water. More cavemen attack, and the spaceman is exposed to the air in the caves, which is toxic to him. Dying, he shows the students several media clips about their disappearance and indicating that humans have left a dying Earth, resettling (and evolving) on Mars. Taylor finds Hopper injured in front of another time dilation, containing his sister, a legion of conquistadors and a cavemen horde virtually frozen in the midst of a battle over control of a waterfall, the source of the time distortion. Hopper explains the field is strongest here, making rescue of his sister impossible; he tells Taylor to go and save the others, as he is also dying. Preparing to leave the cave with the spaceman's ladder, the students are attacked by cavemen before they can get through; Cara is grabbed and pulled through the portal before she can help her friends. From their perspective, she instantly reappears through the portal, futuristically dressed and with tentacle-like mechanisms which pull her friends through. A short time later, Furby awakens, along with Hopper and Hopper's family, all having been retrieved and resurrected with the healing waters. The others arrive, happily explaining they are in a space station and have a lot to talk about.

In 2029 Los Angeles, the Mercy Capital Court responds to a surge in crime by using artificial intelligence (AI) judges to try defendants for violent offenses. To assemble evidence, all devices are also registered to the municipal cloud to allow the AI judge to pass judgement. The AI judge also gives the defendants all available resources to find and provide all the evidence needed to prove their innocence in 90 minutes, or be executed via a sonic blast. Los Angeles Police Department Detective Christopher "Chris" Raven, a strong proponent of the court, is strapped to a chair, put on trial for his wife Nicole's murder, and is given 90 minutes to persuade the AI judge of his innocence. Presiding over his case is the AI Judge Maddox. All the evidence points to Chris having killed his wife, as her blood was found on his clothing and doorbell camera footage places him at their home shortly before her murder. Chris's guilt probability is 97.5%, which qualifies him for execution unless his evidence lowers it to 92% for reasonable doubt and 80% for a Mercy Trial. Since AIs are not allowed to take a human life, the chair is set on a 90 minute timer not controlled by the AI, and it is the defendant’s responsibility to lower their score and this allows the AI to unlock the chair before the timer runs out. Via Maddox's unrestricted access and abilities, Chris learns that Nicole was seeing another man, Patrick Burke. Chris's partner Jacqueline "Jaq" Diallo finds Patrick who confides that Nicole felt unable to communicate her troubles to Chris about work. Her work email records show reports of missing chemicals. Recalling hosting a work barbecue with Nicole, Chris reviews footage to better identify her co-workers. While looking for evidence, Chris confronts his relapse in sobriety following the murder of his former partner, Ray Vale, and regrets not shooting the suspect who was later acquitted. Relapsing into alcoholism led to Chris's aggression toward Nicole, and she began to consider a divorce. Maddox shows Chris records of one co-worker, Holt Charles, who had financial issues and had discussed the chemical disappearance with Robert "Rob" Nelson, Chris's sobriety sponsor. Suspecting Holt may have killed Nicole, Chris tries to contact Rob. Holt instead answers the phone and he explains that Rob is responsible for the missing chemicals. Chris reviews his daughter Britt's social media posts, which reveal that a stranger had been hiding in their basement since the barbecue. His neighbor's security cameras display a rustling in the bushes, and Rob is seen exiting the neighbor's trunk in parking lot surveillance footage. Chris sends Jaq to Rob's house, warning her and her team that he might be armed. The SWAT team arrive at Rob's house, finding it empty, but uncover detailed plans in the shed to craft a bomb. Maddox discovers that Rob's brother, David Webb, who was separated from him after Rob was adopted and given a new name, was the first person Mercy Court executed for murder. Chris realizes that Rob is orchestrating revenge against him and the Court. Chris is officially acquitted for the murder, but refuses to end the trial to exploit Maddox's unrestricted access. He tries to contact Britt, but footage from her grandparents' front door shows Rob kidnapping her and taking her into a stolen semi-truck. A bomb goes off in the shed killing most of the SWAT team. Jaq pursues Rob, who is transporting explosives toward Mercy Court to destroy the building with Chris inside. The police divert Rob away from Mercy Court, and Jaq, assuming command, orders the task force to blow up the truck. Chris pleads with Jaq but she refuses to yield to him. The bomb fails to detonate and Jaq attempts to shoot Rob directly. Rob arrives at Mercy Court, crashing into the building and causing a network glitch that requires a system reset. Maddox reboots in time to release Chris from the chair before the trial ends with his execution. Chris confronts Rob, working with Maddox to distract Rob by having Mercy Court reopen David Webb’s case and demanding Rob to submit his new evidence immediately. Chris then disarms Rob as he speaks and wants to kill him, but is talked down by Britt. Jaq arrives and shoots Rob. Rob provides new evidence that he was on the phone with David when the murder took place, but the police would not listen. Maddox confirms the call's timing and location which placed the phone away from the crime scene. Then Maddox retrieved footage that showed Jaq retrieving that phone from David, removing it from evidence, and dumping it in the river. Jaq explains she wanted to ensure that David was found guilty in the first judgement issued by an AI court to prove the system worked. Jaq and Rob are both taken into custody while Britt reconciles with Chris, whose case is formally dismissed. Maddox and Chris admit mistakes were made by humans and AI and they must learn from their mistakes.

The crew of the joint British and American Space Shuttle Churchill, under the command of Colonel Tom Carlsen, finds a 150-mile-long (240 km) spaceship hidden in the coma of Halley's Comet. Inside, the crew discovers hundreds of desiccated bat-like creatures and three naked humanoid bodies (two male and one female) in suspended animation within glass containers. The crew recovers a bat-alien and the three bodies and begins the return trip to Earth. During the return journey, mission control loses contact with Churchill. A rescue mission discovers that Churchill has been gutted by fire. The crew is dead and the escape pod is missing, yet the three containers bearing the bodies remain intact. The bodies are taken to the European Space Research Centre in London. Prior to a postmortem, the female alien awakens and drains the life force from a guard. She escapes the facility and drains other humans of their life force. The two male vampires awaken and violently attempt escape, but are apparently destroyed by grenades thrown by another guard. The guard drained by the female alien revives two hours after his death, with the ability to drain others of their life force. The Churchill escape pod is found with Carlsen inside. He recounts the events aboard Churchill, including feeling compelled to open the female vampire's container and share his life force with her, leading to the draining of the Churchill crew's life force. He set fire to the shuttle to save Earth from the same fate and escaped in the pod. When hypnotised, it becomes clear that he has a psychic link to the female alien, and he reveals her ability to shapeshift. Carlsen and SAS Colonel Colin Caine trace her to a psychiatric hospital in Yorkshire, where they believe they have trapped her within the heavily sedated body of the hospital manager, Dr. Armstrong. The two male vampires have survived by shapeshifting into the soldiers who killed their previous bodies, and now are infecting London's population. The female alien escapes from her sedated host and disappears. Martial law is declared as vampires multiply by absorbing the life force of humans. The life forces are channeled by the male vampires to the female vampire, who transmits the energy to their spaceship, now in geosynchronous orbit over London. Hans Fallada impales a male vampire with an ancient weapon of "leaded iron." He, Carlsen, and Caine surmise that the vampires have visited Earth periodically with the coming of Halley's Comet, creating the vampire legends. Caine finds Fallada, possessed and manic, and shoots him. Fallada dessicates. Caine retrieves the weapon from a dead corpse which explodes into dust. Carlsen tracks the female vampire to St Paul's Cathedral, where she is lying upon the altar, transferring energy to her spaceship. She reveals she and Carlsen are now a part of each other due to the sharing of their life forces. Caine kills the second male vampire and throws the weapon to Carlsen, who impales himself and the female alien simultaneously. A burst of energy blows open the dome of St Paul's. The two ascend the column of energy to the spaceship, which returns to the comet as Caine watches.