In the 1920s, in the town of Hillsboro, Tennessee, a female voice sings " Old-time Religion " as schoolteacher Bertram Cates is arrested for violating state law by conducting a lesson on Charles Darwin 's Descent of Man. The event makes headlines around the world. Matthew Brady, statesman, three-time presidential candidate, and Biblical scholar, volunteers to assist Prosecutor Tom Davenport. A huge parade welcomes Brady, who asks Rev. Jeremiah Brown to stand beside him as he addresses the crowd. Witty and cynical E.K. Hornbeck of the Baltimore Herald, an influential newspaperman, seizes the opportunity to announce that Cates's defense attorney, provided by the newspaper, will be the equally well-known Henry Drummond, one of America's most controversial legal minds and a notorious agnostic. Tourists flood the town. Welcoming Drummond, Hornbeck takes him on a tour of the circus Hillsboro has become. Meanwhile, in the courtroom, Judge Coffey deals with reporters, photographers, and local political interests. Later at the hotel, Brady, his wife Sarah, and Drummond reminisce, regretting the loss of the close friendship they once had. That night, Rev. Brown rallies the townspeople, calling down God's vengeance. When his daughter Rachel, who is engaged to Cates, protests, he condemns her. Admonishing Brown’s harshness, Brady quotes Proverbs 11:29: "He that troubleth his own house shall inherit the wind," sending the crowd home. Breaching Rachel’s confidence to him and Sarah, Brady calls Rachel to the stand, compelling her to tell how Cates left the church when her father declared that a child who drowned was not worthy of heaven because he was not baptized. Overzealously, Brady browbeats a distressed Rachel; Cates instructs Drummond not to cross-examine her, even though her testimony of Cates’s doubts has damaged him with the jury. Drummond intends six scientists as witnesses, but the prosecution successfully objects. Frustrated, Drummond gives an impassioned speech of the consequences of allowing an outdated law to prevail, turning progress backward. He asks to withdraw from the case. The judge orders him to show cause the next morning why he should not be held in contempt. John Stebbins, the father of the drowned boy, offers his farm as collateral for Drummond's bail. That night, the crowds march with a burning effigy chanting that Cates should be hanged. When Drummond tells Hornbeck he needs a miracle, Hornbeck tosses him a Bible, scornfully exclaiming, "Here's a bagful!" Drummond clasps the Bible to his chest, smiling. In court, Drummond makes the unprecedented move of calling Brady—the opposing counsel —as an expert on the Bible, since he has been barred from presenting scientific experts. Brady welcomes this challenge, but he becomes increasingly flustered by Drummond's questions on Biblical inconsistencies and absurdities, such as the “seven days” of creation and Jonah surviving being swallowed by a whale. Brady admits to being unfamiliar with Darwin’s On the Origin of Species. Exposed for his lack of intellectual curiosity, a humiliated Brady is forced to admit that Biblical passages cannot be interpreted literally. He falls into Drummond’s trap to cast doubt on the Bible as the sole credible explanation for human existence. WGN Radio is in court to announce the guilty verdict. Bowing to political pressure not to give a harsh punishment that would aggravate global opinion of Hillsboro backwardness, the judge fines Cates only $100, which Drummond says he will appeal. A disappointed Brady tries to enter a speech into the record, but Drummond successfully moves that the court be adjourned and the crowd begins to leave. As Brady attempts his speech, which few remain to hear, he collapses and dies. Alone in the courtroom, planning the obituary, Hornbeck asks Drummond what Brady said to Rev. Brown, to which Drummond cites Proverbs 11:29 chapter and verse. Hornbeck marvels at how Drummond can quote scripture yet call himself an agnostic. Drummond accuses Hornbeck of being a heartless cynic, a lonely man who will be buried alone. As he leaves, Hornbeck responds confidently that Drummond will be there. Drummond picks up the Bible and Darwin's book in either hand, balancing them as the voice from the beginning sings, " Mine eyes have seen the glory …". Drummond slams the books together, and he walks out with them under his arm.

Mark Whitacre, a rising star at the Archer Daniels Midland (ADM) office in Decatur, Illinois, during the early 1990s, blows the whistle on the company's price-fixing tactics at the urging of his wife Ginger. One night in November 1992, Whitacre confesses to FBI special agent Brian Shepard that ADM executives—including Whitacre himself—had routinely met with competitors to fix the price of lysine, an additive used in the commercial livestock industry. Whitacre secretly gathers hundreds of hours of video and audio over several years to present to the FBI. Whitacre assists in gathering evidence by clandestinely taping the company's activity in business meetings at various locations around the globe. These include locations in Tokyo, Paris, Mexico City, and Hong Kong. He eventually collects enough evidence of collaboration and conspiracy to warrant a raid of ADM. Whitacre's good deed dovetails with his own major infractions, while his internal, secret struggle with bipolar disorder seems to take over his exploits. Whitacre's meltdown results from the pressures of wearing a wire and organizing surveillance for the FBI for three years, instigated by Whitacre's reaction, in increasingly manic overlays, to various trivial magazine articles he reads. In a stunning turn of events immediately following the covert portion of the case, headlines worldwide report Whitacre had embezzled $9 million from his own company. This happened simultaneously while he was covertly working with the FBI and taping his co-workers. Whitacre also aims to be elected as ADM CEO following the arrest and conviction of the remaining upper management members. In the ensuing chaos, Whitacre appears to shift his trust and randomly destabilize his relationships with Special Agents Shepard and Herndon and numerous attorneys in the process. Authorities at ADM begin investigating the forged papertrail Whitacre had built to cover his own deeds. After being confronted with evidence of his fraud, Whitacre's defensive claims begin to spiral out of control, including an accusation of assault and battery against Agent Shepard and the FBI, which had made a substantial move to distance their case from Whitacre entirely. Due to this major infraction and Whitacre's bizarre behavior, he is sentenced to a prison term three times as long as that meted out to the white-collar criminals he helped to catch. In the epilogue, Agent Herndon visits Whitacre in prison as he videotapes a futile appeal to seek a presidential pardon. Overweight, balding and psychologically beaten after his years long ordeal, Whitacre is eventually released from prison, with Ginger awaiting to greet him.

Prominent Paris art collector Charles Bonnet forges and sells famous artists' paintings. His disapproving daughter, Nicole, constantly fears his being caught. Late one night at their mansion, Nicole encounters a burglar, Simon Dermott, holding her father's forged " Van Gogh ". She threatens him with an antique gun that accidentally fires, slightly wounding his arm. Wanting to avoid an investigation that would uncover her father's fake masterpieces, Nicole does not contact the police, and instead drives the charming Simon to his lavish hotel in his expensive sports car, then takes a cab home. Charles is lending the Kléber-Lafayette Museum his renowned " Cellini " Venus statuette for an exhibition. The statue was actually sculpted by his father. Charles has never sold it, knowing scientific testing would reveal it as a fake, rendering his entire collection suspect. Charles signs the museum's standard insurance policy, unaware it includes a forensic examination. Withdrawing the Venus from the exhibition would raise suspicions. Desperate to protect her father, Nicole asks Simon to steal the Venus before the examination. He claims it is impossible to steal the Venus, but changes his mind upon realizing he has fallen for Nicole. American tycoon Davis Leland, an avid art collector, is obsessed with owning the Venus. He arranges to meet Nicole solely to purchase the statue, but finds her attractive. At their second meeting, Leland proposes marriage to ensure he can obtain the statue, but Nicole hurriedly accepts his ring as she rushes off to the museum for the "heist". Nicole and Simon hide in the museum's utility closet until closing time. After observing the guards' routine, Simon repeatedly sets off the security alarm using a toy boomerang until the "faulty" system is finally disabled. Simon notices Nicole's resemblance to the Venus, and she admits that her grandmother posed for the statue that her grandfather sculpted; Simon admits knowing that the Venus was fake and only agreed to the heist for her. Simon takes the Venus, and Nicole, disguised as a cleaning woman, hides it in a bucket. When the Venus is discovered missing, they escape in the ensuing chaos. Following the robbery, Leland seeks to acquire the Venus by any means. Simon offers to "sell" it to him on condition that it never be displayed to anyone and that he never contact the Bonnet family again; Simon says Leland will be contacted later for payment. Leland runs from Nicole when she tries to return the engagement ring; Simon later secretly adds the ring to boxed statue before giving it to Leland, who immediately leaves the country with it. Nicole meets Simon at the Ritz Hotel to celebrate their success, though she is stunned when he admits it was his first heist. Simon is actually an expert consultant and investigator hired by major art galleries to enhance security and detect forgeries. He was investigating Charles' art collection when Nicole first encountered him. When Charles unexpectedly arrives, Simon assures him that the statue will soon be safely out of the country. Charles is relieved though momentarily disappointed that there will be no $1 Million insurance payment due to the statue never being authenticated. Simon insists Charles give up forgery, to which he agrees. As Nicole and Simon are on their way to get married, a collector who admired Charles's new "Van Gogh" arrives at the Bonnet residence. Nicole tells Simon that it is his father's "cousin". Simon admires her newfound flair for lying, and they drive off to begin their new life together.

In an airport, Lone Man is being instructed on his mission by Creole. The mission itself is left unstated and the instructions are cryptic, including such phrases as "Everything is subjective," "The universe has no center and no edges; reality is arbitrary," and "Use your imagination and your skills." After the meeting at the airport, he travels to Madrid and then on to Seville, meeting several people in cafés and on trains along the way. Each meeting has the same pattern: he orders two espressos at a cafe and waits, his contact arrives and in Spanish asks, "You don't speak Spanish, right?" in different ways, to which he responds, "No." The contacts tell him about their individual interests such as molecules, art, or film, then the two of them exchange matchboxes. Inside each matchbox that Lone Man receives, is a code written on a small piece of paper. He reads them, and then eat the paper. These coded messages lead him to his next rendezvous. He repeatedly encounters a woman who is always either completely nude or wearing only a transparent raincoat. She invites him to have sex with her but he declines, stating that he never has sex while he is working. One phrase that Creole, the man in the airport, tells him is repeated throughout the movie: "He who thinks he is bigger than the rest must go to the cemetery. There he will see what life really is: a handful of dirt." This phrase is sung in a peteneras flamenco song in a club in Seville at one point in his journey. In Almería, he is given a ride in a pickup truck - driven by a companion of the Mexican - on which the words La vida no vale nada ('life is worth nothing') are painted, a phrase Guitar says to him in Seville, and he is taken to Tabernas desert. There lies a fortified and heavily guarded compound. After observing the compound from afar, he somehow penetrates its defenses and waits for his target inside the target's office. The target asks how he got in, and he answers, "I used my imagination." After garroting the target with a guitar string, he rides back to Madrid, to the room where he disrobes from his latest fresh suit. Folding it, and locking it away, he changes into a sweatsuit bearing the national flag of Cameroon. Before exiting the train station onto a crowded sidewalk he throws away his last matchbox.

Chance Buckman is the head of a Houston -based oil-well firefighting outfit. With a team that includes Joe Horn, Greg Parker, and George Harris, Chance travels around the world putting out blazes at well heads from industrial accident, explosion, or terrorist attack. Chance enjoys the thrills, but longs for ex-wife Madelyn. She divorced him 20 years earlier, taking their daughter Letitia with her, because Madelyn could not bear to see her husband risk his life. Though they love each other, Madelyn could not deal with her terror that Chance might be badly injured or burn to death in a fire. While extinguishing a burning wellhead, Chance suffers a near-fatal accident when he is crushed by a bulldozer blade. Against his wishes, his daughter Letitia (Tish) visits him in the hospital, summoned by his old friend and former firefighting partner Jack Lomax and fetched by Greg Parker in the Buckman Company's corporate jet. She also pursues Greg Parker to a well fire in Louisiana despite Greg's notorious reputation for using fires to pick up women (generally, any woman he takes to a fire ends up in bed with him). In the case of Buckman's spitfire of a daughter, however, after considerable initial friction, Greg and Tish fall in love and marry five days after their first meeting. In spite of Greg's reputation, Buckman comes to trust his daughter's choice and accepts Greg into the family. Madelyn, projecting her own fears onto her daughter, though gracious, is rather less accepting, despite her liking for Greg. Greg suspects that his new father-in-law is growing increasingly protective of him after the marriage in an effort to protect his daughter from heartbreak should her new husband be harmed or killed. Tish wishes to see the fires that her husband and father fight, which neither man encourages. Her father relents and allows her to accompany Greg into the field. Chance, trying to reunite with his ex-wife, leaves the Buckman Company to accept an executive position with his old friend Jack Lomax on the board of directors of Lomax Oil as a way to win her back. Chance gives his company to his son-in-law as a "wedding present", although Greg's pride compels him to tell Buckman he "doesn't want any gifts" and that he will "pay twice what it's worth." Greg and Tish begin traveling the world to put out oil fires. Soon, the older couple announce that they will remarry, to the delight of Tish. Madelyn is happy to see her husband in a safe job, but before too long, Chance becomes bored with corporate life and longs to be back in the field. As Jack Lomax earlier told Tish, "Your father is the best there is at what he does. No man can walk away from that." Greg encounters problems with a fire in Venezuela —five oil wells in a tight line burning all at once, further compounded by guerrillas who are trying to undermine the operation. He asks Chance to return and help fight the fire. Chance does so without hesitation. Buckman goes to Venezuela in a Texas Air National Guard transport full of firefighting gear, unaware that Madelyn and Tish have followed him to Caracas. Madelyn uses Jack Lomax's influence with the president of Venezuela to get Tish and herself to the oilfield where the fire is burning. Madelyn declares "This is it for me," in the sense that it will either make or break her ability to deal with the fires once and for all, fully aware that her relationship with Chance is on the line. The Hellfighters put out the fires with the help of the Venezuelan Army, while under attack by rebel warplanes that strafe the oilfield. Madelyn explodes in anger at what she perceives as the Venezuelans' inability to protect the team from the unexpected air raid, railing at the Venezuelan army and civil officials for allowing the guerrillas to get close enough to attack. Chance pulls her away during her tirade. She snaps, "Damned if I understand your attitude!", to which he replies, "It's very simple—you'll do." When Greg asks Tish for her take on it, she just smiles and says, "I think we ought to get her a tin hat," referring to the bright red hardhats with the Buckman Company logo worn by the Hellfighters.

In 1968, English businessman Donald Crowhurst is inspired by Sir Francis Chichester to compete in the Sunday Times Golden Globe Race, a single-handed, round-the-world yacht race. Though only an amateur sailor, Crowhurst believes that technology and gumption will enable him to succeed in a custom trimaran, thus ensuring financial security for his wife and young children. As delays and costs mount, however, Crowhurst is forced to sign promissory notes pledging his company and home to his main sponsor Stanley Best, should he fail to finish. Barely ready in time for the race, Crowhurst must complete the race or lose everything he holds dear. During his trip in the Teignmouth Electron he attempts to give an optimistic version of events to both his family and press agent, but inwardly feels under pressure due to his financial situation, physical danger and loneliness. The film cuts between his voyage and scenes at home where his wife Clare is attempting to deal with the situation. To make matters worse for Crowhurst, his boat is damaged, making his journey forward extremely risky. He begins to falsify his records, greatly exaggerating how far he has sailed each day. Crowhurst decides to be vague in his communications, hinting to the newspapers that he is rounding the cape of Africa, while instead sailing slowly and attempting to go unnoticed before returning home. He surreptitiously lands in Argentina to repair the boat. At home, his apparent success is bringing significant press attention. Robin Knox-Johnston completes the race, but Crowhurst’s false accounts suggest that he will finish the fastest as all other sailors but one have dropped out of the race. Crowhurst slows down his return trip to avoid the attention that finishing fastest would bring, knowing that scrutiny would reveal he had fabricated his earlier location reports. Upon learning that the other sailor still in the race has also dropped out because of his false records, he becomes overwhelmed with guilt and fear. He starts to lose his mind and begins to hallucinate and imagines seeing his wife who he confesses to. As his mental health fails, so does his physical health and he is oblivious to harming himself as he attempts to stay occupied by maintaining the radio. Meanwhile the vessel drifts. As his family, the press and public expectantly wait for his return, he loses all control of his mind and his situation and in despair realises he cannot go home and only has one way out. His vessel is eventually found adrift without Crowhurst onboard. It is not clear if he has jumped or fallen overboard. The authorities deduce from his records that he has lied about his progress during his journey. In the closing credits it states that Crowhurst‘s body was never found and that he was at sea for 7 months and completed 13,000 miles. Robin Knox-Johnston was the only sailor to finish the race and he donated his prize money to Crowhurst‘s family.

Charlie Cartwright, an amorous English tour guide, takes groups of Americans on whirlwind nine-countries-in-18-days sightseeing tours of Europe. Having overslept with his newest conquest, he is late meeting tour #225, finding a resentful group eager to start. Samantha Perkins, one of those tourists, is on vacation to contemplate whether to marry her fiancé, George. In London, Charlie begins a campaign to charm and seduce the gorgeous Samantha, who considers him frivolous and conniving, reluctant to become just another conquest. Despite verbal sparring, they become mutually attracted, and the confirmed bachelor Charlie proposes marriage. Samantha ultimately decides to settle for neither the unexciting George, who turns up unexpectedly, nor the charismatic Charlie, who is unsuitable husband material. Fred and Edna Ferguson take their daughter Shelly on the trip to separate her from an undesirable boyfriend with whom she is getting sexually involved. In Amsterdam, Shelly meets an activist American college student who follows her around different tour locations, where they sneak off on his motorcycle to spend time together sightseeing through counterculture eyes. Also in Amsterdam, Irma Blakely disappears on a Japanese tour bus she mistakenly boards when separated from her group. Multiple attempts must be made before the two tours overlap to restore her to her husband, Harve. Although Harve pines for Irma during the whole trip and must be coaxed into joining the group at a nightclub, when Irma finally reappears in Rome, she finds him onstage dancing with burlesque dancers and mistakenly believes he has been partying in her absence. Irma declares they will go to Japan next year, since she has made many friends on her improvised tour. In Belgium, Jack Harmon revisits the World War II site where he fought in Bastogne. As he tells tall tales to a fellow tourist, Freda Gooding, of a German retreat, he literally crosses path with a German veteran who is acting out a contradictory tale of Allied retreat to his wife. In Rome, eager to see Gina, a woman he met during the war, again, Jack's fantasies are shattered when he finds that, while still attractive, she is now a grandmother with a family. In consolation, he turns to Freda Gooding, a widow, and begins to get to know her. Often getting slapped, Bert Greenfield sneaks pictures of breasts, thighs, and other intimate angles of voluptuous women, pretending that he is "scoring" with them, and sending made-up stories to his buddies. Desperate, he pays a pretty girl to pose with him in an embrace; she returns his money out of pity and kisses his cheek before departing. In Italy, John Marino takes time from the tour to meet his relatives, who receive him warmly but alarm him when they want to fix him up with Francesca, a plump, plain cousin, who he jumps through a bathroom window into a canal to avoid. The next day he is handed a pile of messages from “a cousin” and spends the rest of his time avoiding her. As he is leaving Venice, John finds that he has been dodging a different―beautiful―cousin he laments not getting to know; Bert laments not getting her photo for his collection. Throughout the tour, Fred complains to Edna that the tour is an ordeal and he is eager to get home. His one objective is to have a custom pair of Italian shoes made, for which he goes through an arduous process to make the non-English-speaking shoemaker understand his specifications. After Fred leaves, the shoemaker selects a pair of ready-made shoes from a catalogue, completely mistaking the specifications, that he will mail to the U.S. to fulfill the "special order". Despite having complained throughout the whole tour, Fred declares they will go on a tour of Scandinavia next year. Throughout the tour, kleptomaniac Harry Dix steals "souvenirs" such as towels, ashtrays, Bibles, bells, lifesavers, telephones, and paintings from each location, which he stows into a commodious suitcase. At the airport on departure, his suitcase is so heavy that it collapses, spilling all his pilfered objects, which he leaves behind. Starting tour #226, Charlie gives an introductory speech evoking unexpected adventure, reflecting his new romantic, less cynical, outlook, as the new group of tourists rotate seats and get to know each other.

In November 2001, Mohamedou Ould Slahi is in Mauritania, two months after the September 11 attacks. A Mauritanian policeman tells Mohamedou that Americans want to have a talk with him. Mohamedou agrees to go with them. In Albuquerque, New Mexico, in February 2005, lawyer Nancy Hollander is told by French lawyer Emmanuel that a lawyer from Mauritania approached his firm in Paris on behalf of Mohamedou's family. They haven't seen Mohamedou since he was arrested three years ago and only just found out in a newspaper that he is being held by the United States at the Guantanamo Bay detention camp and is accused of being one of the organizers of 9/11. Emmanuel asks Nancy to look into it because she has a security clearance from a previous case and can ask questions he can't. Nancy agrees to check. At a Naval Law Conference in New Orleans, Marine Prosecutor Stuart Couch is told by Colonel Bill Seidel about the Mohamedou case which Seidel wants him to prosecute. Seidel says that Mohamedou fought with Al-Qaeda in the '90s and then recruited for them in Germany, and says it was Mohamedou who recruited the terrorist who flew Stu's friend's plane into the tower. Nancy and Teri (her fellow lawyer) fly down to Guantánamo to meet Mohamedou. Mohamedou agrees to hire them as his lawyers. Meanwhile, Stu tells his team to go through all the intel reports they have to corroborate the story against Mohamedou. Nancy finds out something through Mohamedou's letter which she received from him while Stu looks at the MFR (Memorandum for the Record), showing exactly what happened. The letter and reports talk about enhanced interrogation methods (i.e., torture) and other maltreatment including sexual assault upon Mohamedou by the Guantanamo guards as ordered by General Mandel. General Mandel also threatened the arrest and rape of his mother. Thus, to save his mother and to get the torture to stop, Mohamedou gave a false confession about being a terrorist. Stu withdraws from Mohamedou's prosecution in disgust. In December 2009, at trial Mohamedou testified over video link to the court. In March 2010, Mohamedou received a letter informing him that his case was successful, and the judge has ordered him to be released. Text is shown telling us that it would be another 7 years before he actually was released, because the government appealed. His mother died in 2013 so he never saw her again. He was finally released in 2016, having spent 14 years in prison without ever being charged. Finally, footage of the real Mohamedou arriving back in Mauritania is shown. Texts are shown, telling us Mohamedou lives in Mauritania and got married in 2018 to an American lawyer. They have a son, Ahmed, but haven't been able to live together as a family and are hoping a country will grant them protection and citizenship. Nancy and Teri are still lawyers working against injustice, and we see footage of Mohamedou giving them necklaces with their names in Arabic.

In late 1941, during World War II, the United Kingdom struggles to halt Nazi Germany 's attempts to take over Europe, with London regularly bombed by the Luftwaffe and supply and aid ships constantly sunk by German submarines. Brigadier Colin Gubbins initiates Operation Postmaster, a covert sabotage mission to disrupt U-boat resupply operations on Spanish-controlled Fernando Po. SOE agents Marjorie Stewart and Richard Heron depart by train while Gubbins enlists Gus March-Phillipps to assemble a ground team to destroy the Italian supply ship Duchessa d'Aosta and two tugboats. Gus and his allies Henry Hayes, Freddy Alvarez, and Danish Army officer Anders Lassen sail to Fernando Po on the neutral Swedish fishing trawler Maid of Honor. They divert to a German-controlled section of La Palma to rescue SOE saboteur Geoffrey Appleyard from the Gestapo. Gubbins had sent Appleyard ahead hoping Gus would want him on the team. Marjorie and Heron use an 'illegal' gambling hall on Fernando Po to recruit backup for Gus's team. Marjorie seduces Heinrich Luhr, the SS commander in charge. Learning that the Duchessa intends to depart three days early, Gus sails through a British naval blockade of Nazi-occupied West Africa knowing they'll be arrested if their unauthorised mission is discovered. Marjorie and Heron learn that Luhr has had the Duchessa's hull reinforced despite the Italian attache's reservations. Gus and Appleyard decide their best course of action is to hijack the ships and use them for barter after a mole in Gubbins's staff reveals the mission to senior command. Luhr catches on when Marjorie's act begins to 'slip' but the raid is successful, and Marjorie shoots Luhr in the head. Delivering the boats to a British fleet outside Lagos, the team is arrested. They are spared court-martial when Winston Churchill adds them to his 'Ministry of Ungentlemanly Warfare'. A montage before the end credits reveal the later activities of several protagonists: Gus became a war hero helming similar raids and married Marjorie at the start of her acting career; Appleyard received commendations for his role in the mission, much to the king's amusement; Hayes became an accomplished spy notable for surviving a year of Nazi torture; Lassen took part in raids outside the group until his death in 1945; Ian Fleming, part of Gubbins's inner circle, used Operation Postmaster as inspiration for his James Bond novels.

Anthropologist Stanley Shephard is brought to an arctic base when explorers discover the body of a prehistoric Neanderthal caveman who has been frozen for 40,000 years. After thawing the body to perform an autopsy, the scientists detect brainwaves on the EEG monitor and proceed to successfully resuscitate the "iceman." The dazed Neanderthal is alarmed by the surgical-masked figures; only Shephard has the presence of mind to remove his mask and reveal his humanity and somewhat familiar (bearded) face, permitting the iceman to settle into a peaceful recuperating sleep. The scientists place the iceman in an artificial, simulated environment for study, though the iceman quickly deduces that he is far from home. Shephard believes that the iceman's culture may provide clues to learning about the human body's adaptability, citing ceremonies such as firewalking. Other scientists see the potential in studying the iceman's DNA and his survival in the ice, for possible "freezing" of the sick until treatment is possible. Shephard defends the iceman's right to be considered a human being and not a scientific specimen. Despite opposition from the others, Shephard initiates an encounter with the iceman. Shephard names him "Charlie" after the iceman introduces himself as "Char-u." Shephard and Charlie bond, but it becomes obvious to the anthropologist that Charlie misses his world. A linguist is brought to the Arctic base, and the scientists make progress communicating with Charlie. Shephard introduces Charlie to Shephard's colleague, Dr. Diane Brady. Assuming that the woman is Shephard's mate, Charlie makes lines in the sand that indicate that he likely was a man with a mate and children before he was frozen. Shephard strives to understand what motivates Charlie and why he survived being frozen. At one point, Shephard begins to sing " Heart of Gold ", inspiring Charlie to sing one of his own songs. Charlie's line drawings in the ground resemble a bird, matching body markings on his chest. When the base's helicopter strays over the roof of Charlie's area, he takes on an obsessive zeal as he climbs toward the roof. Shouting the word Beedha, he lifts his arms toward the helicopter in a sign of worship. Even though the helicopter pulls away from the dome, Shephard knows that Charlie can now think of nothing else. Shephard consults local Inuit who recognize the name that Charlie chanted and explain that it is a mythical bird, a messenger for the gods. Shephard understands that Charlie has a spiritual side and that he was on a dreamwalk pilgrimage, a mythical quest for redemption. His people were dying in the sudden ice age; he must have offered himself to the gods in the form of a self-sacrifice or an appeal to the gods to redeem his tribe. Charlie escapes after watching Shephard exit the biosphere. In a panic of seeing unfamiliar modern devices, and believing they are his enemies, he accidentally spears Maynard, one of the base's technicians, before being recaptured, and Shephard's experiment is put to an end. However, Shephard helps Charlie escape into the wild. Charlie races on ahead of Shephard as they pass by glaciers and ice shelves; a crevasse opens up in front of Shephard, cutting him off from Charlie. When the helicopter emerges over an ice shelf, Shephard looks on helplessly as Charlie grabs hold of one of its landing skis. In an attempt to evade Charlie's grasp, the helicopter pilot pulls up, but Charlie dangles beneath the aircraft while it continues to climb high into the sky. Charlie is ecstatic, believing the "messenger" is taking him to his god. He releases his grip, seeming to float through the sky while he plunges to his death. Shephard's initial horror turns into joy, as he realizes that Charlie has reached his "dreamwalk" goal that he began 40,000 years earlier, even though it means his death.

During the Great Fire of Rome in AD 64, Emperor Nero "fiddles". Tigellinus informs Nero that he is suspected of starting the fire. Nero instead has the fire blamed on the Christians. In Rome, the Apostle Titus, Mercia, and Favius are apprehended by a mob for being Christians. Marcus Superbus, the prefect of Rome, arrives and disperses the mob, allowing the Christians to go free. News of Marcus's mercy towards the Christians spreads throughout Rome, including to Empress Poppaea. At a fountain, Marcus meets with Mercia again; there, Licinius reads Nero's edict to Marcus reminding him of his duty to arrest Christians. Later that night, Titus sends Stephan, a young Christian man, to tell other Christians of the secret meeting at the Cestian Bridge. Shortly after, Marcus arrives at Mercia's home wanting to take her for himself, but Mercia decides to stay. Stephan is arrested by Licinius under suspicion of being a Christian. In a dungeon, under torture Stephan reveals the location of the Christians' secret meeting. After learning of Stephan's arrest and torture, Marcus races to the meeting hoping to save Mercia. Along the way, he crashes into Poppaea's carriage. She demands Marcus stay, but he leaves her and promises to be with her in the morning. At the meeting, Roman soldiers surround the Christians, and Titus and some members of his congregation are struck dead by arrows. Marcus arrives at the meeting and saves Mercia, and takes her home, while the other Christians are arrested and imprisoned. The next morning, Poppaea scolds Marcus for his affections to Mercia. Elsewhere in the palace, Tigellinus informs Nero of Marcus's disobedience to his edict. Nero accuses Marcus of betrayal. Jealous of Mercia, Poppaea influences Nero to sign an order for Mercia's arrest. At a feast in Marcus's home, he introduces Mercia to Ancaria, who performs an exotic dance. Outside, Ancaria's performance is drowned out by the Christians' singing. Annoyed by the singing, Marcus sends his party away so he may be alone with Mercia. He tries to get Mercia to renounce her Christian faith so she may be with him, but she refuses. Shortly after, Licinius arrives to arrest Mercia, who is to be executed for treason amongst one hundred Christians in the arena. Marcus returns to Nero's palace and demands that the emperor spare Mercia, but Nero refuses. In the arena, the audience is entertained by several spectacles, including gladiator battles. When the time for the Christians' execution arrives, Mercia is told to stay behind by Poppaea's orders, as she is to be executed alone. In the arena, the Christians are mauled to death by lions. Following the execution, Marcus again asks for Mercia to renounce her faith and be his wife. Mercia refuses once more, but she states that she loves him. Refusing to live without her, Marcus accompanies Mercia, and they are both executed.

In 1985 New York, Connor MacLeod encounters an old enemy, Iman Fasil, in the parking garage of Madison Square Garden. After a sword duel, Connor beheads Fasil and absorbs a powerful release of energy from his body, then hides his sword in the garage's ceiling. NYPD officers detain him on suspicion of murder but lack evidence to hold him. Connor's history is revealed through a series of flashbacks. In the Scottish Highlands in 1536, Connor fights against the rival Fraser clan as a warrior of the MacLeod clan. The Frasers are aided by an outlander knight in exchange for his right to slay Connor. In battle, the knight fatally stabs Connor but is driven off by his clansmen. After Connor makes a complete recovery, his lover Kate and his cousin Dougal accuse him of witchcraft. The clan wants to kill him, but his other cousin, chieftain Angus, mercifully exiles him. Connor quietly settles into a new life as a blacksmith and marries a woman named Heather MacDonald. Juan Sánchez-Villalobos Ramírez, a wandering swordsman, seeks out Connor. He explains that they and others like them are " Immortals ". They possess a sixth sense known as the "quickening" and can be killed only by beheading. Each immortal must be ready to do battle with others, save on holy ground. Ramírez trains Connor in sword fighting and the two become friends. He informs Connor that as the number of immortals dwindles, they will gather in a distant land for a final confrontation until only one remains with the combined quickening of all. Immortals cannot conceive children, and Ramírez urges Connor to leave Heather so that he will be unburdened in the fight ahead. The knight that he encountered, the Kurgan, is a powerful and vicious immortal who would subject humanity to an eternity of darkness. One night while Connor is away, the Kurgan finds Ramírez at his home with Heather and decapitates him in a duel. Connor stays with Heather until she dies of old age, leaving him heartbroken. He adopts Ramírez's katana as his own and spends the next few centuries wandering the Earth. In 1985, the Gathering approaches, and the Kurgan comes to New York, where Connor deals antiques under the alias "Russell Nash", assisted by his confidant and adopted daughter Rachel Ellenstein. Brenda Wyatt, a metallurgy expert working for the police as a forensic scientist, finds shards of Connor's sword at Fasil's death scene and is puzzled that the sword smithing techniques do not match the age of the blade. She follows Connor for clues and witnesses the Kurgan attacking him. The police arrive, forcing them to flee. She meets with Connor twice afterward, hoping to learn about the paradoxical sword. Connor likes her but tells her to leave him alone. The Kurgan duels and beheads Sunda Kastagir, another immortal. A witness to the fight gives the NYPD a description of him. Brenda investigates Connor and finds evidence that he has lived for centuries. On Heather's birthday, Connor lights a candle for her in a church as he has done every year. The Kurgan arrives and confirms that he and Connor are now the last remaining immortals and also reveals he raped Heather after killing Ramírez. Disgusted, but prohibited from fighting on holy ground, Connor leaves. Brenda confronts Connor, who explains his true identity. After spending the night together, they part company, but the Kurgan finds out about their newfound intimacy and kidnaps Brenda to draw Connor out. Connor decides to leave behind the Russell Nash identity, says goodbye to Rachel, and confronts the Kurgan at Silvercup Studios in Queens, rescuing Brenda in the process. After a long duel, Connor outfights and decapitates the Kurgan, absorbing his power. Connor returns to Scotland with Brenda and reveals that he is now a mortal man who can age and have children. He is also able to read the thoughts and feelings of people all around the world, and remembering Ramírez's lessons, he hopes to encourage cooperation, understanding, and peace among humanity.