About 10,000 years ago, peaceful aliens from the planet Antarea established an outpost on Earth, on Atlantis. When Atlantis sank, 20 aliens were left behind, kept alive in rock-like cocoons at the bottom of the ocean. A group of Antareans have returned to collect them. Disguising themselves as humans, they rent a house with a swimming pool and charge the water with "life force" to give the cocooned Antareans energy to survive the trip home. They charter a boat, the Manta III, from a local captain named Jack, who helps them retrieve the cocoons. Jack spies on Kitty, a beautiful woman from the team who chartered his boat, while she undresses in her cabin, and discovers that she is an alien. After the aliens reveal themselves to him and explain what is going on, he decides to help them. Next door to the house the Antareans are renting is a retirement home. Three of its residents—Ben, Arthur, and Joe—often trespass to swim in the pool. They absorb some of the life force, making them feel younger and stronger. Caught in the act, they are permitted to use the pool by the Antarean leader, Walter, on the condition that they do not touch the cocoons or tell anybody else about it. Kitty and Jack grow closer and decide to have sex in the pool. Since she cannot do so in the human manner, she introduces him to the Antarean equivalent, in which she shares her life force energy with him. The other retirement home residents become suspicious after witnessing Mary, Ben's wife, climb a tree. Their friend Bernie mindlessly reveals the secret to the other residents, who rush to the pool to swim. When Walter finds them damaging one of the cocoons, he ejects them from the property. The Antareans open the damaged cocoon, and the creature inside shares his last moments with Walter. That evening, Bernie finds that his wife Rose has stopped breathing and carries her body to the pool to heal her, only to be informed by Walter that the pool no longer works due to the other residents draining the life force in the rush to make themselves young. Walter explains that the cocoons cannot survive the trip back to Antarea but will be able to survive on Earth. With the help of Jack, Ben, Arthur, and Joe, the Antareans return the cocoons to the sea. The Antareans offer to take residents of the retirement home to Antarea, where they will never grow older and never die. Most of them accept the offer, but Bernie chooses to remain on Earth. Upon leaving, Ben tells his grandson David that he and Mary are leaving for good. As the residents are leaving, David's mother, Susan, finds out about their destination and drives to the retirement home, where they find the majority of the rooms vacant and contact local authorities. While the police are searching for the residents in the dark, David notices Jack's boat being started, with the Antareans and the retirement residents aboard. He runs toward it, and as the Manta III pulls away from the dock, leaps across the gap, clings to its side, and is pulled aboard by Ben. The boat is chased by the Coast Guard, so David says goodbye to Ben and Mary before jumping into the sea. The Coast Guard boats stop to pick him up, giving the others a chance to get away. A thick, mysterious fog appears suddenly, stranding the Coast Guard boats and causing the Manta III to disappear from their radar, so they call off the chase. As the Antarean ship appears overhead, Walter pays Jack for his services and his boat. Jack embraces Kitty for the last time, and they kiss. He then says farewell to everyone before jumping into an inflatable life raft as the Manta III rises into the Antarean vessel. Jack watches as it disappears inside the ship and departs. Back on land, a memorial service is held on a beach for the missing residents. During the sermon, David looks toward the sky and smiles.

In 2017, following a worldwide economic collapse and resource scarcity, the USA has become a totalitarian police state. The government maintains control through propaganda and censorship of unsanctioned art, music, and communication. The state-controlled broadcaster ICS runs the nation's most popular program, "The Running Man," a game show in which prisoners can earn their freedom by surviving as "runners" against lethal "stalkers". Captain Ben Richards is arrested after refusing orders to open fire on an unarmed food riot in Bakersfield. His fellow officers massacre the rioters and frame Richards for the incident, branding him the "Butcher of Bakersfield". 18 months later, Richards escapes from a prison labor camp with resistance fighters Harold Weiss and William Laughlin. They ask him to join their cause, but Richards declines, focused only on surviving. Richards travels to his brother's former apartment but discovers that ICS composer Amber Mendez now lives there after his brother was taken for "re-education". Richards forces Amber to help him bypass airport security, but thinking he is the "Butcher", she alerts the authorities. After his capture, Amber sees news reports falsely claiming that Richards murdered people during the incident and begins to doubt his guilt. Damon Killian, host of The Running Man, approaches Richards hoping to use his notoriety to revive the show's ratings. He threatens to send the recaptured Weiss and Laughlin into the game unless Richards agrees to participate. As the show begins, Killian betrays Richards by sending him, Weiss, and Laughlin into the game zone—an abandoned section of L.A.—via rocket sleds. The group is hunted by Subzero, a hockey-themed stalker whom Richards kills, marking the first time a runner has ever killed a stalker. Meanwhile, Amber is caught retrieving the uncut Bakersfield footage and is sent into the zone. Killian sends in two more stalkers—the chainsaw-wielding Buzzsaw and the electricity-shooting Dynamo. Richards kills Buzzsaw, though Laughlin is fatally wounded. Weiss discovers that the satellite uplink controlling government broadcasts is located inside the zone, and he cracks the access code for Amber to memorize before Dynamo kills him. Richards incapacitates Dynamo but refuses to kill him while he is defenseless, shocking the audience. When Killian secretly offers Richards a job as a stalker, Richards angrily refuses. Amber later finds the corpses of Whitman, Price, and Haddad, the show's supposed past "winners", realizing their victories were fabricated, and Richards kills the flamethrower-wielding Fireball. The audience begins cheering for Richards. Richards and Amber are found by resistance leader Mic and taken to their command center. Killian tries to force retired stalker Captain Freedom to fight Richards, but he refuses unless he can fight him honorably. ICS instead fabricates footage showing Freedom killing Richards and Amber. Seeing this broadcast, Richards realizes that the government must ensure they are never seen alive again. Using the satellite uplink codes, Mic transmits an exposé revealing Killian's and the government's lies, including the unedited Bakersfield footage, while Richards leads resistance fighters in a takeover of ICS to prevent the broadcast from being shut down. The resistance battles ICS security forces as the studio audience flees. Dynamo attempts to rape Amber, but she activates the sprinkler system, electrocuting him. Richards confronts Killian, forces him into a rocket sled, and sends him into the game zone, where the uncontrolled vehicle crashes and explodes, killing him. Richards and Amber kiss as the crowd celebrates, and the broadcast goes offline.

In 2047, a distress signal is received from the Event Horizon, a spaceship that disappeared during its maiden voyage to Proxima Centauri seven years earlier. The ship has mysteriously reappeared in orbit around Neptune, prompting the US Aerospace Command to dispatch the Lewis and Clark rescue vessel to investigate. Its crew members—Captain Miller, second-in-command Lieutenant Starck, pilot Smith, medical technician Peters, engineer Justin, doctor D.J., and rescue technician Cooper—are joined by Dr. William Weir, who designed the Event Horizon. Shortly before arrival at the Event Horizon, Weir briefs them on the ship's experimental gravity drive with a simple visualization of how it folds spacetime to instantly transport the ship across vast distances. He then plays them the distress signal, which consists of screams, howls, and what sounds like a voice. D.J. recognizes it as the Latin phrase "līberāte mē", which he translates as "save me". Upon boarding the Event Horizon, the crew finds signs of a massacre. As they search for survivors, the ship's gravity drive activates and briefly pulls Justin into a portal before unleashing a shock wave that breaches the hull of the Lewis and Clark. The crew is forced to move to the Event Horizon while Cooper rescues Justin from the portal, finding that he has been reduced to a catatonic state. Smith and Cooper are sent on a spacewalk to repair the hull of the Lewis and Clark while the rest of the crew begin to experience hallucinations of their biggest fears and regrets. Miller sees Eddie Corrick, a subordinate from a previous journey who he left to die in order to save the other crew members. Peters sees her son with his legs covered in bloody lesions, while Weir sees a vision of his late wife, now eyeless, urging him to join her. Justin suddenly wakes from his coma while the entire ship seems to be shaking and attempts to vent himself from the airlock; he is saved at the last second by Miller, who places a severely injured Justin in stasis. Shaken, Miller confides in D.J. about his hallucinations, prompting D.J. to reveal that he found a longer phrase in the distress signal. It really says "libera te tutemet ex inferis", which he translates as "save yourself from Hell ". D.J. concludes that the ship's drive must have opened a gateway to somewhere beyond the known universe and brought something horrible back with it. His conclusion gains more credibility when a video log is discovered on the Event Horizon, showing the ship's crew members horrifically brutalizing each other after engaging the gravity drive, with their captain chanting in Latin as he holds his own eyeballs in his hands. Miller immediately orders his crew to speed up their evacuation, ignoring Weir's protests to the contrary. Miller and Smith retrieve CO2 scrubbers from the Event Horizon as Peters is lured to her death by a hallucination of her son. Weir finds her body and is flung into a hallucination of his wife's suicide, driving him to gouge out his own eyes and embrace the ship's evil presence. Now corrupted, he uses an explosive to destroy the Lewis and Clark, killing Smith and blasting Cooper into space before killing D.J. by vivisecting him. Miller confronts Weir on the bridge but is overpowered. Weir initiates a 10-minute countdown to activate the gravity drive and return the ship to the hellish dimension. Meanwhile, Cooper uses his spacesuit's oxygen supply to propel himself back to the ship and appears at the bridge window. Weir shoots at him, shattering the window and blowing himself into space with the decompression. Miller, Starck, and Cooper survive and manage to seal off the ship's bridge. With their own ship destroyed, Miller plans to split the Event Horizon in two with explosives and use its forward section as a lifeboat. He is attacked by hallucinations which turn out to be the resurrected and even more mutilated Weir. Miller fights him at the gravity drive and detonates the explosives, sacrificing himself to save his remaining crew. The gravity drive activates, pulling the ship's stern into a black hole. Starck and Cooper enter stasis beside a comatose Justin and wait to be rescued. 72 days later, the wreckage of the Event Horizon is boarded by a rescue party who discover the survivors in stasis. Starck hallucinates Weir as one of the rescuers and screams but she quickly awakens, realizing that it was only a nightmare. Cooper and the rescue team try to calm the terrified Starck as the doors close.

In 2154, Earth is overpopulated, diseased, and heavily polluted from ecocide. The planet's citizens live in extreme poverty. In contrast, the rich and powerful live on Elysium, an orbiting space station just outside Earth's atmosphere, with luxuries including Med-Bays, medical devices that can heal any disease or condition. Spider, a hacker living in Los Angeles, runs a space shuttle operation to smuggle people into Elysium. Elysium Defense Secretary Delacourt is in charge of preventing illegal entry to Elysium. She orders hired killer Kruger to shoot down Spider's space shuttles. Elysium President Patel reprimands Delacourt for her unorthodox methods, threatening to terminate her position for any more unauthorized actions. Patel then discharges Kruger. In retaliation, Delacourt offers Armadyne Corp CEO John Carlyle defense contracts for life if he creates a program allowing Delacourt to conduct a coup and install herself as president. Carlyle writes the program and stores it inside his brain. On Earth, parolee Max Da Costa works for Armadyne Corp when he is accidentally exposed to a lethal dose of radiation. He is only given medication for the side effects and told he has five days to live after being fired by Carlyle. Max and his friend Julio approach Spider to bargain: if Max successfully steals information from an Elysium citizen, Spider will give Max a shuttle ride to Elysium to use a Med-Bay to cure his condition. Max demands that the target be his former boss, Carlyle. Due to his declining health, Spider provides Max with a powerful exoskeleton via surgery. Max and Julio shoot down Carlyle's shuttle to Elysium; Carlyle is fatally injured in a shootout against his security robots. Max and Julio successfully extract the program from his brain, but the data becomes unexpectedly scrambled, locked behind a security program. Delacourt sends Kruger and a black ops team to retrieve it. Kruger kills Julio, but an injured Max escapes with the copy of the program, while Carlyle's death destroys any possibility of further retrieval from his brain. Max seeks help from his childhood friend and nurse, Frey, whose daughter has leukemia. After she patches him up, Max goes to Spider. He realizes that the data in Max's head is a program that can reboot the entire Elysium mainframe. Delacourt locks down all flights up to Elysium, leaving Spider unable to take Max. Max angrily leaves, though not before Spider discreetly places a tracking device on him. After Kruger kidnaps Frey and her daughter, Max approaches him and offers him the data for the use of a Med-Bay. Kruger accepts, and Delacourt lifts the lockdown so the group can travel to Elysium. During the flight, Kruger and Max fight over the data, and a grenade explodes in Kruger's face, damaging the ship. The ship then crashes on Elysium; Max is arrested and taken to Delacourt, who orders a team to extract the data. Max escapes and heads to the armory to save Frey, who has been turned over to Kruger's men. Kruger is revived by a Med-Bay and confronted by Delacourt, whom he fatally wounds. He orders his men to start killing the politicians on the station while he dons a more advanced exoskeleton suit to hunt down Max, planning to initiate the protocol himself. Spider lands on Elysium and finds Max. Max wants Spider to have his men protect Frey and get her daughter to a Med-Bay to be healed. They reach the computer core, where they are confronted by Kruger. Max and Kruger engage in combat, which ends with Max managing to disable Kruger's connection to his suit; Kruger responds by attempting to kill them both with a grenade, but Max throws him over the ledge as the grenade explodes, killing Kruger. Spider connects Max to the computer, but the data transfer will kill Max if he downloads it. Max says his goodbyes to Frey and initiates the download, killing him. The Elysium computer reboots, allowing Frey to heal her daughter. The robot police arrive but cannot arrest Spider, as everyone on Earth is now considered a citizen of Elysium. Medical shuttles loaded with Med-Bays are dispatched to Earth to heal everyone who needs help.

In the dystopian future, sexual intercourse and reproduction are prohibited, and mind-altering drugs are mandatory to enforce compliance among the citizens and to ensure their ability to conduct dangerous and demanding tasks. Workers wear identical white uniforms and have shaven heads to emphasize uniformity, likewise with police androids who wear black and monks who are robed. Instead of names, people have designations with three arbitrary letters (referred to as the "prefix") and four digits, shown on an identity badge worn at all times. At their jobs in central video control centers, SEN 5241 (a man) and LUH 3417 (a woman) keep surveillance on the city. LUH has a male roommate named THX 1138, who works in a factory producing android police officers. At the beginning of the story, THX finishes his shift, while the loudspeakers urge the workers to "increase safety"—and congratulate them for only losing 195 workers in the last period—to the competing factory's 242. On the way home, he stops at a confession booth. A Christ -like portrait of "OMM 0000" intones reassuringly as he worries that his sedatives are not working and LUH has been acting strangely. At home, THX takes his drugs and watches holobroadcasts while engaging with a masturbatory device. LUH secretly substitutes pills in her possession for THX's medications, causing him to develop nausea, anxiety, and sexual desires. LUH and THX become involved romantically and have sex. THX is later confronted by SEN, who attempts to arrange that THX become his new roommate, but THX files a complaint against SEN for the illegal shift pattern change. Without drugs in his system, THX falters during a critical and hazardous phase of his job, and a control center engages a "mind lock" on THX, which raises the level of danger. After the release of the mind lock, THX makes the necessary correction to that work phase. THX and LUH are arrested and THX undergoes drug therapy and medical analysis. He enjoys a brief reunion with LUH, but it is disrupted shortly after she reveals her pregnancy. At THX's trial, it is stated that THX was clinically born. It is decided that it would be inefficient to terminate THX, so THX is sentenced to prison, alongside SEN. THX and SEN walk to search for an exit. Eventually they are joined by hologram actor SRT 5752, who starred in the holobroadcasts. SRT shows them the exit and suggests to them that they may have been going in circles. During the escape, THX and SRT are separated from SEN. Chased by the police androids, THX and SRT are trapped in a control center, from which THX learns that LUH has been "consumed", and her name has been reassigned to her fetus, numbered 66691, in a growth chamber. SEN eventually escapes to an area reserved for the monks of OMM, where a monk notices that SEN has no identification badge. SEN attacks him and later wanders into a child-rearing area, strikes up a conversation with children, and sits aimlessly until police androids apprehend him. THX and SRT steal two cars. SRT struggles to figure out how to drive the car. When SRT finally gets the car to move, he immediately crashes his car into a concrete pillar. After the crash, SRT is not found in the vehicle. Pursued by two police androids on motorcycles, THX flees to the limits of the city. Android officers continue to pursue him as he briefly struggles with simian-like creatures identified as "shell dwellers" and arrives at a vertical shaft with an escape ladder. The android officers are ordered by Central Command to cease pursuit, on the grounds that the expense of his capture exceeds their allocated budget for THX. In a last-ditch attempt to convince THX to surrender, the officers claim that the area outside the "city shell" is uninhabitable, but he is undeterred and continues up the ladder. The city is then revealed to be entirely underground, while THX has escaped onto the surface, where he witnesses the sun setting.

In the future, all forests on Earth have become extinct from careless environmental exploitation. As many specimens as possible have been preserved in a series of enormous greenhouse-like geodesic domes serving as closed ecological systems attached to large cargo spaceships, forming part of a fleet of eight " American Airlines Space Freighters", stationed outside the orbit of Saturn. Freeman Lowell, one of four crewmen, is the resident botanist and ecologist on one of these ships, the Valley Forge. He carefully maintains a variety of plants for their eventual return to Earth and the reforestation of the planet. He spends most of his time in the domes, cultivating the crops and attending to the animal life. The crew of each ship receives orders to jettison and destroy their domes and return the freighters to commercial service. After four of the six Valley Forge domes are jettisoned and destroyed with nuclear charges, Lowell rebels and opts to save his ship's plants and animals. He kills John Wolf, one of his crewmates who arrives to plant explosives in his favorite dome, and his right leg is seriously injured in the process. He then jettisons and triggers the destruction of the other remaining dome to trap and kill the remaining two crewmen. Enlisting the aid of the ship's three service robots, Lowell stages a fake premature explosion as a ruse and sends the Valley Forge speeding toward Saturn in an attempt to hijack the ship and flee with the last forest dome. He then reprograms the drones to perform surgery on his leg and sets the Valley Forge on a risky course through Saturn's rings. Later, as the ship endures the rough passage, Drone 3 is lost, but the ship and its remaining dome emerge relatively undamaged on the other side of the rings. Lowell gives the surviving drones the names Dewey (Drone 1) and Huey (Drone 2), while the lost Drone 3 is named Louie (a nod to Disney characters Huey, Dewey, and Louie). Lowell, Huey, and Dewey set out into deep space to maintain the forest. Lowell reprograms Huey and Dewey to plant trees and play poker. He also has them bury Wolf in the bio-dome. Lowell begins speaking to them constantly, as if they are children. Huey is damaged when Lowell accidentally collides with him while driving a buggy recklessly, and Dewey sentimentally refuses to leave Huey's side during the repairs. As time passes, Lowell is horrified when he discovers that his bio-dome is dying, but is unable to come up with a solution to the problem. When the Berkshire —another space freighter waiting to see if the Valley Forge has survived the trip around Saturn—eventually reestablishes contact, he knows that his crimes will soon be discovered. It is then that he realizes a lack of light has restricted plant growth, and he races to install lamps to correct this situation. In an effort to save the last forest before the Berkshire arrives, Lowell jettisons the bio-dome to safety. He then detonates nuclear charges, destroying the Valley Forge, the damaged Huey, and himself in the process. The final scene is of the now well-lit forest greenhouse drifting into deep space, with Dewey tenderly caring for it, holding Lowell's battered old watering can.

In the future, humanity is preparing to launch an attack on the homeworld of an alien race, called the Formics, that had attacked Earth and killed millions. The Formic invasion was stopped by Mazer Rackham, who crashed his fighter jet into the Formic queenship at the apparent cost of his life. Over the course of 50 years, gifted children are trained by the International Fleet to become commanders of a new fleet for a counterattack. Cadet Andrew "Ender" Wiggin draws the attention of Colonel Hyrum Graff and Major Gwen Anderson because of his aptitude in simulated space combat so is recruited into Battle School. In the school he is placed with other cadets his age, but Graff treats him as extraordinary, thereby subjecting him to ostracism. The cadets are placed in squads and perform training games in a zero-gravity "Battle Room". Ender quickly adapts to the games, devising new strategies older students had not contemplated. However, Ender is also annoyed that the leaders do not let students read their emails, as they believe it will distract them. Graff reassigns Ender to Salamander Army, led by Commander Bonzo Madrid. Bonzo, disgusted that the replacement he asked for is an untrained student, forbids Ender from training with the rest of the squad. Cadet Petra Arkanian takes him under her wing and trains him privately, much to Bonzo's chagrin. In the next match, Bonzo forbids Ender from participating in a battle between the Salamander Army and another team. However, seeing the team losing and Petra in trouble, Ender comes to her aid and helps Salamander Army win, regardless of the fact that he has disobeyed orders. Ender plays a computerized "mind game" set in a fantasy world, which presents difficult choices to the player. In one situation, Ender creates an outside-the-box solution to overcome a seemingly unsolvable problem. Later, he encounters a Formic in the game, and then simulated images involving his psychotic brother, Peter, and compassionate sister, Valentine. Anderson notes these unusual additions to the game are seemingly altered by Ender's interaction with it. Graff promotes Ender to lead his own squad, which is made up of misfit students. They are put in increasingly difficult battles. In a surprise match against two other teams, including Bonzo's Salamander Army, Ender devises a novel strategy of sacrificing part of his team to achieve a goal, impressing Graff. After the match, Bonzo attacks Ender out of rage, but Ender fights back, resulting in Bonzo hitting his head and sustaining a serious injury. Bonzo is then briefly seen in the infirmary receiving emergency surgery, leaving his ultimate fate ambiguous. Distraught, Ender quits Battle School, but Graff has Valentine convince him to continue. The group's training is rigorous, and Anderson expresses concern over this, but Graff notes they have run out of time. Graff takes Ender to humanity's forward base on a former Formic planet near their homeworld to meet with Rackham, who explains that the Formics share a hive-mind mentality and how he exploited it to win the battle. Ender finds that his former squad members are also there to help him train in computerized simulations of large fleet combat; Rackham puts special emphasis on the fleet's Molecular Detachment (MD) Device that is capable of disintegrating matter. Ender's final test is monitored by several fleet commanders. As the simulation starts, Ender finds his fleet over the Formic homeworld, vastly outnumbered. He orders most of his fleet to sacrifice themselves to protect the MD long enough to fire on the homeworld. The resulting chain reaction burns the entire planet. The simulation ends, and Ender believes the test is over. The commanders restart the video screens, showing that Ender's fleet was in a live mission, destroying the Formic homeworld. Despite Graff congratulating him, Ender becomes livid, having been tricked into killing a race that had never re-attacked Earth. While asleep, Ender is awoken by the Formic Queen and is directed to a Formic structure nearby as being similar to the ruined castle from the game. She acknowledges Ender's role in the genocide and moves to kill him, but when he shows remorse, she spares his life. The dying Queen gives Ender a Queen egg that she has been protecting. With the war ended, Ender is promoted to Admiral, given a small ship, and left to his own devices. In a letter to Valentine, he confides that he is going into deep space, determined to find a suitable planet to start a new Formic colony with the Queen egg.

Medical student Nelson Wright convinces classmates Joe Hurley, David Labraccio, Rachel Manus, and Randy Steckle to help him discover what lies beyond death. Nelson flatlines for one minute before his classmates resuscitate him. While "dead", he sees a boy he bullied as a child, Billy Mahoney. He merely tells his friends that he cannot describe what he saw, but something is there. The others follow Nelson's feat. Joe flatlines next and experiences an erotic sequence linked to his promiscuous lifestyle. After arguing with Rachel and out-bidding her of the length of time that they are willing to remain “dead”, David is third to flatline on Halloween and sees a girl, Winnie Hicks, whom he bullied in grade school. The three men later start to experience hallucinations related to their visions. Nelson gets physically assaulted by Billy Mahoney twice. Joe, engaged to be married, is haunted by the women that he secretly videotaped during his sexual dalliances, who taunt him with the same false promises he used on them. On a train, David is confronted by the 8-year-old Winnie, who taunts him the way he taunted her. Rachel decides to flatline next. David rushes in, intending to stop the others from giving her their same fate, but arrives too late. Rachel nearly dies when the power goes out and the men cannot shock her with defibrillator paddles. She survives, but she too is haunted by the memory of her father dying by suicide when she was young. The three men reveal their harrowing experiences to one another, and David decides to put a stop to his visions. Meanwhile, Joe's fiancée, Anne, comes to his apartment and, having discovered his videos, ends their relationship. Joe's visions cease after Anne leaves him. David goes to visit a now adult Winnie and apologizes. She accepts his apology and thanks him, who feels a weight lifted off his shoulders. David then finds Nelson, who accompanied him to visit Winnie, beating himself with an axe. In Nelson's mind, Billy is again attempting to beat him to death. David stops him, and they return to town, where Rachel confronts Nelson about withholding the supernatural nature of the experiments from the rest of them, then storms off. David later instructs Joe and Randy to help Nelson find Billy. Having an idea of what Rachel has experienced, David offers to let her stay with him and they fall asleep together. Meanwhile, Nelson takes Randy and Joe to a graveyard. He killed Billy as a kid by throwing rocks until he fell out of a tree. They try to convince Nelson that what he did was accidental, but he does not listen. They are eventually stranded when Nelson storms off in Joe's Mustang. David leaves Rachel to rescue Joe and Randy at the cemetery. While alone, she goes to the bathroom and finds her father. He apologizes to Rachel, whose guilt over his death is lifted after he reveals he was addicted to morphine and his suicide was related to post-traumatic stress disorder resulting from his tour in Vietnam. Nelson calls David's house, and when Rachel answers he tells her he needs to flatline again to make amends. He apologizes for involving her and their friends in his reckless plan. The three men realize what he intends and race to stop Nelson, who has been dead for nine minutes when they arrive. Together with Rachel, the four friends work to save him. In the afterlife, the boy Nelson is in the tree being stoned by Billy from the ground and dies from the subsequent fall. When almost all his friends are about to give up on reviving Nelson, Billy forgives him. David gives Nelson one last shock, which brings him back.

Unemployed brothers Bob and Doug McKenzie screen a poorly made film they have produced. When the disappointed patrons become hostile, the brothers release a jar of moths into the theater, which disrupts the showing and allows them to escape without issuing refunds, although they do give one refund to two crying children, which turns out to be the beer money their father gave them. The next day, the two place a live mouse in an empty beer bottle in an attempt to blackmail the local beer store into giving them free beer from Elsinore Brewery, but they are told to take their complaint to Elsinore Brewery's management. When they do so, they are given jobs on the bottling line inspecting for mice in bottles. Meanwhile, the evil Brewmeister Smith is developing a plan to take over the world by adulterating Elsinore beer with a mind control drug which, while rendering the consumer docile, also makes them vulnerable to mind control when certain tones are played. Smith tests this spiked beer on patients of the neighbouring Royal Canadian Institute for the Mentally Insane, which is connected to the brewery by tunnels. Bob and Doug learn that the brewery's former owner, John Elsinore, has recently died under mysterious circumstances and his daughter Pam has inherited the family castle and been given full control of the brewery. While exploring the massive complex, they find a shuttered cafeteria containing an old Galactic Border Patrol video game, which supernaturally reveals that Brewmeister Smith murdered John Elsinore and that Pam's bumbling Uncle Claude was involved. Bob recognizes a brewery employee as former hockey great Jean "Rosie" LaRose, who suffered a career-ending nervous breakdown and has fallen under Smith's control. Eventually, Bob and Doug wander into the Brewmeister's operations room while he is away, and Doug takes a floppy disk containing a video of John Elsinore's murder (thinking it is a " new wave EP bootleg " and not realizing the importance of its contents). Smith and Claude tranquilize the brothers and arrange to frame them for murder, concealing Pam and her father's friend, Henry Green, in beer kegs in the back of their sabotaged van, and instruct the brothers to deliver the kegs to a party. Unable to stop, the brothers careen into Lake Ontario. All survive (Pam with apparent memory loss), and the brothers are arrested. The brothers' bizarre antics at their trial cause the judge to declare them insane and put them under Brewmeister Smith's care at the asylum. Rosie soon finds them and helps them escape, and they find and rescue Pam. Having figured out the Brewmeister's plan, Rosie foments an uprising among the brainwashed mental-patient test subjects. The brothers separate for the first time in their lives. Doug and a group of asylum inmates help capture Claude, while Rosie and another group overpower Brewmeister Smith. The spirit of John Elsinore, possessing the brewery's electrical system, electrocutes Smith when he is shoved against his light-up world map. Meanwhile, Smith has locked Pam and Bob in a brewery tank and begins filling it with beer; they escape when Bob consumes all the beer, expanding to a cartoonish size. John Elsinore's ghost warns them that Smith has already shipped tainted beer to Oktoberfest and urges them to prevent the beer from being consumed. The police accompany the brothers back to their house to retrieve their dog, Hosehead, to invade the party. Enticed by promises of free beer and sausages, Hosehead leaps into the air and flies over the city like a superhero. He crashes into the tent at the celebration and, mistaken for a skunk, frightens people away from the tainted beer. In the end, the McKenzie Brothers are heroes and Pam and Rosie find true love. Bob and Doug are allowed to haul away the contaminated beer, apparently to try to drink it all. The film ends with an over-the-credits commentary by Bob and Doug about the film and select crew members as their names scroll by in the credits.

Federal Marshal William O'Niel is assigned to a tour of duty at the titanium ore mining outpost Con-Am 27, operated by the company Con-Amalgamated on the Jovian moon of Io. Conditions on Io are difficult; gravity is 1/6 that of Earth's with no breathable atmosphere, and spacesuits are cumbersome with limited air. Shifts are long but significant bonuses are paid. The general manager, Mark Sheppard, boasts that productivity has broken all records since he took over. Carol, O'Niel's wife, feels she cannot raise their son Paul on Io and leaves with him to the Jupiter space station to await a shuttle back to Earth. Cane, a miner, enters an elevator without his spacesuit during a psychotic episode and dies from decompression. Tarlow, another miner, suffers an attack of stimulant psychosis — he sees spiders and rips open his spacesuit — resulting in death by explosive decompression. With the reluctant assistance of Dr. Lazarus, O'Niel investigates the deaths. Another incident involves a worker, Sagan, who takes a prostitute hostage and threatens to kill her with a knife. O'Niel attempts to calm the man while Montone, his sergeant, sneaks in via the air duct and kills Sagan with a shotgun. O'Niel and Lazarus discover that Sagan had traces of polydichloric euthimal, a powerful amphetamine -type drug in his bloodstream, which would allow a miner to work continuously for days at a time until they burn out and turn psychotic after approximately ten months of use. O'Niel uncovers a drug distribution ring run by Sheppard and sanctioned by now repentant Montone. Using surveillance cameras, O'Niel finds and captures Nicholas Spota, one of Sheppard's dealers, who is murdered before he can be questioned. Montone is found garrotted. In a meat locker, O'Niel finds the latest shipment of drugs, which was shipped from the space station. He is attacked there by another dealer, Russell Yario. O'Niel, wearing an anti-garrotting collar, knocks him out, then destroys the shipment of drugs. When Sheppard finds out, he threatens O'Niel and contacts his drug distributor, asking him to send in professional hitmen. O'Niel is prepared, having hacked into Sheppard's communications. O'Niel waits for the arrival of the hitmen on a supply shuttle from the other side of Jupiter. Realizing what is coming and with only Dr. Lazarus willing to help him, O'Niel sends a message to his family promising to return to Earth when his "job is done". O'Niel ambushes the assassins one by one. Lazarus helps him kill the first by trapping him in a pressurized corridor; O'Niel activates a bomb, causing an explosive decompression that kills the man. The second is killed in a glass greenhouse structure of the outpost when O'Niel tricks him into shooting a window, causing it to break open and blow him out to his death. O'Niel is then confronted and attacked by Sheppard's inside man — one of his own deputies, Sgt. Ballard. The two fight outside the outpost near the satellite structure until O'Niel pulls Ballard's oxygen hose, suffocating him as he pushes him into an electrical generation station, vaporizing him on impact. O'Niel then confronts the surprised Sheppard inside the outpost's recreation bar, knocking him out with one punch. It is implied Sheppard will now be brought to justice or murdered by his own associates. O'Niel, however, has already contacted his superiors about Sheppard's associates, some of whom are Con-Am executives, and shortly before his departure receives a communication that warrants have been issued for their arrests. O'Niel bids farewell to Lazarus and leaves on the shuttle to join his wife and son on the journey back to Earth.

Nerdy social outcast students Gary Wallace and Wyatt Donnelly of Shermer High School are humiliated by senior jocks Ian and Max for swooning over their cheerleader girlfriends Deb and Hilly. Humiliated and disappointed at their direction in life and wanting more, Gary convinces the uptight Wyatt that they need a boost in popularity in order to win their crushes away from Ian and Max. Alone for the weekend with Wyatt's parents gone, Gary is inspired by the 1931 film Frankenstein to create a virtual woman using Wyatt's computer, infusing her with everything they can conceive of to make the perfect dream woman. After they hook electrodes to a doll and hack into a government computer system for more power, a power surge creates Lisa, a beautiful and intelligent woman with reality-altering powers. She promptly produces a pink 1959 Cadillac Eldorado convertible to take the boys to a blues dive bar in Chicago, using her powers to procure fake IDs for them. They return home drunk, where Chet, Wyatt's mean older brother, extorts $175 from Wyatt in exchange for his silence. Lisa agrees to keep herself hidden from him, but she realizes that Gary and Wyatt, while sweet, are very uptight and need to unwind. After another humiliating experience at the mall when Max and Ian pour a slushie on Gary and Wyatt in front of a crowd, Lisa tells the bullies about a party at Wyatt's house, before driving off in a Porsche 928 she conjured for Gary. Despite Wyatt's protests, Lisa insists that the party take place. She meets Gary's parents, Al and Lucy, who are shocked and dismayed at the things she says and her frank manner, to Gary's embarrassment. After she pulls a stainless steel.44 Magnum handgun on them (later revealed to Gary to be a water pistol), she alters their memories so that Lucy forgets about the conflict; however, Al forgets altogether that they have a son. At the Donnelly house, the party has spun out of control. Gary and Wyatt take refuge in the bathroom, where they resolve to have fun despite having embarrassed themselves in front of Deb and Hilly. In Wyatt's bedroom, Ian and Max convince Gary and Wyatt to recreate the events that created Lisa, but the process fails. Lisa chides them over their misuse of the process to impress their tormentors. She also explains that they forgot to connect the doll; thus, with the bare but live electrodes resting on a magazine page showing a Pershing II medium-range ballistic missile, a real missile emerges, erupting through the floor and ceiling of the house. Meanwhile, Wyatt's grandparents arrive and confront Lisa about the party, but she places them in a frozen, catatonic state and hides them in a kitchen cupboard. Lisa realizes that the boys need a challenge to boost their confidence and has a gang of mutant bikers crash the party, causing chaos and terrorizing the guests. The bikers take Deb and Hilly hostage. Wyatt and Gary confront the bikers, which causes Deb and Hilly to fall in love with the boys. The bikers leave. The next morning, Chet returns from duck hunting to discover his home in disarray: A localized snowstorm fills his room, and a huge missile stands in the middle of the house. Lisa has the boys escort the girls home while she talks to Chet alone. Gary and Wyatt proclaim their feelings, and both girls reciprocate. Returning to the house, the boys discover Chet, now transformed into a foul, talking toad-like creature. He apologizes to Wyatt for his behavior. Upstairs, Lisa assures them that Chet will soon return to normal, and, realizing that her purpose is complete, tearfully hugs both Gary and Wyatt before de-materializing. As she leaves, the house is "magically" cleaned and everything transformed back to normal, including Chet. Wyatt's parents return home, completely unaware that anything unusual has happened. Later, Lisa turns up as the new gym teacher at Shermer High School.