The film is divided into three parts from the point of view of the main characters.

In 1918, a man named Burt Berendsen is sent by his estranged wife's parents to fight in World War I. While stationed in France, Burt befriends African-American soldier Harold Woodman. After sustaining injuries in battle, Burt and Harold are nursed back to health by nurse Valerie Bandenberg. After the end of the war, the three live together in Amsterdam. Burt returns to New York City to be with his wife. Harold begins a romantic relationship with Valerie. Valerie, however, eventually abandons Harold, who also returns to New York. Fifteen years later, Burt has opened his medical practice treating veterans of the war. Harold is now a lawyer, and they have not heard from Valerie since they left Amsterdam. Harold asks Burt to perform an autopsy on Bill Meekins (a senator who served as the commander of their regiment during the war) at the behest of Meekins's daughter Elizabeth, who believes that he was murdered during his recent trip to Europe. Aided by medical examiner Irma St. Clair, Burt performs the autopsy, which reveals poison in Meekins's stomach. Burt and Harold meet with Elizabeth to talk about the autopsy results, but she is soon killed when a hitman pushes her into traffic. The hitman frames Burt and Harold for her death, and they flee as the police arrive. Burt and Harold try to find out who told Elizabeth to hire them. This leads them to wealthy textile heir Tom Voze, his patronizing wife Libby, and Tom's sister Valerie (whose real surname is Voze). Valerie had persuaded Elizabeth to hire them, knowing that they were trustworthy. Valerie is under constant supervision by Tom and Libby, who claim that she suffers from a nerve disease and epilepsy. They were actually poisoning Valerie to keep her compliant. Burt and Harold talk with Tom, who suggests that they talk to General Gil Dillenbeck, a notable veteran who is friends with Meekins, to learn who accompanied Meekins on the trip (and might have poisoned him or be able to lead them to the person who did). While Burt attempts to contact the general, Irma visits him at his medical practice. She says that she was attacked and her wrist broken while trying to bring him the autopsy report, and the attacker took the paper from her. After resetting her wrist, Burt kisses Irma. Meanwhile, Harold and Valerie notice that the hitman, Tarim Milfax, has been watching the house. They follow him to a forced sterilization clinic owned by an organization known as the "Committee of the Five". After a fight with Milfax, Harold and Valerie reunite with Burt. Valerie takes them to the Waldorf Astoria New York. There, they meet Paul Canterbury and Henry Norcross, Valerie's benefactors from Amsterdam. They are secretly spies in the intelligence community. The Committee of the Five is a cabal in the US with ties to Germany and plans to overthrow the American government. Dillenbeck can help foil their plot. The trio meets with Dillenbeck, who is offered a large sum of money from a man on behalf of an unnamed benefactor to deliver a speech advocating for veterans to forcibly remove U.S. President Franklin D. Roosevelt and install Dillenbeck as a puppet dictator instead. Dillenbeck agrees to help the trio foil the plot and to speak at a veterans reunion gala that Burt and Harold are hosting to draw out whoever is behind the plot. At the gala, Tom introduces Dillenbeck to the industrial leaders Nevins, Belport and Jeffers. Burt realises that they actually want Dillenbeck to become the fifth member of their cabal. Dillenbeck reads his speech instead of the one he was paid to read. Milfax tries to shoot him, but Harold, Valerie, and Burt stop him in time. Milfax is arrested and the Committee of the Five is revealed to be four industry leaders, including Tom. They intended to turn the United States into a fascist country. Tom and the other leaders are arrested by the police, but do not stay in jail long, and expose Dillenbeck in the press following their release. Dillenbeck testifies about the incident to Congress. Harold and Valerie leave the country since they cannot be together in the United States. Burt wishes them farewell, planning to reopen his medical practice and pursue a relationship with Irma.

After the town of Kaihoro's entire population disappear, the Astro Investigation and Defence Service (AIDS) sends their agents Derek, Frank, Ozzy, and Barry to investigate. They find the town overrun by man-eating aliens disguised as humans in blue shirts. Barry kills one of the aliens and is attacked by others. After Derek notifies Frank and Ozzy, he begins torturing Robert, an alien they caught earlier. Robert's screaming attracts a number of aliens. Derek kills the would-be rescuers, but he is attacked by Robert and falls off a cliff ledge, to his presumed death. Meanwhile, charity collector Giles passes through Kaihoro. He escapes Robert's attack and comes to nearby house for help, only to get captured by another alien. Giles later wakes up in a tub of water filled with vegetables and is told he is about to be cooked and eaten. Derek wakes up in a seagull 's nest with a hole in his head, so he uses a hat to keep his brains from leaking out. That night, Frank, Ozzy, and Barry infiltrate the aliens' house and find a room filled with bloody cardboard boxes, likely containing the corpses of former Kaihoro residents. They kill an alien, and Frank wears its shirt to infiltrate their meeting. He learns that the victims have been harvested for food and hears of their recent hostage, Giles. The alien later dines on Robert's vomit, and the disguised (and disgusted) Frank has to follow suit. He escapes and tells the others of the plan. They save Giles as the aliens sleep. At sunrise, they try to leave but are attacked by the aliens, and a gunfight ensues. Derek emerges and joins the fight, using his belt as a headband when the hat is shot off. He grabs a chainsaw from the boot of his car and heads for the aliens' house. As the group leaves with Giles, the alien leader (Lord Crumb) and his followers morph into their true form and follow. Ozzy uses a rocket launcher to explode Frank's car, which has been overrun by aliens. Frank and Ozzy hunt for Lord Crumb and kill many aliens along the way. Meanwhile, Derek kills an alien with his chainsaw and replaces the missing parts of his brain with its brain. An alien prepares to shoot Frank and Ozzy, but it is beheaded by Derek. Frank and Ozzy are shocked to see him alive, and see he has lost his mind. After they escape the house, Lord Crumb shoots Ozzy in the leg and Frank fires his rocket launcher at the leader, but misses. Lord Crumb knocks out Derek and the house transforms into a giant spaceship and blasts off into space. On board, Derek looks out the window to see Earth. He ambushes Crumb and kills the alien with his chainsaw. He proclaims war on the alien, then puts on the alien leader's skin and laughs maniacally as he rockets towards the alien planet. Back on Earth, the survivors drive away in Derek's car.

In 1987, two university students in an unnamed Romanian town, Otilia Mihărtescu and Gabriela "Găbița" Drăguț, are roommates in a dormitory. When Găbița becomes pregnant, the two young women arrange a meeting with Mr. Bebe in a hotel, where he is to perform an illegal abortion. At the college dorm, Găbița and Otilia review the items they need for the day. As Găbița nervously sits and waits, Otilia bargains and buys soap and cigarettes from the dormitory shop. Afterwards, Otilia takes a bus to visit her boyfriend Adi, from whom she borrows money. Adi asks Otilia to visit his family that night, as it is his mother's birthday. Otilia initially declines but relents after Adi becomes upset. Otilia heads to the Unirea hotel, where Găbița has booked a room, only to be informed by an unfriendly receptionist that there is no reservation under Găbița's last name. Otilia visits another hotel, the Tineretului, and after much begging and haggling, is able to book a room at an expensive rate. After speaking with Găbița on the telephone, Otilia goes to a rendezvous point to meet with Bebe, although he had asked Găbița to meet him personally. Mr. Bebe grows angry upon hearing that Găbița is not at the planned hotel. At the Tineretului, Bebe discovers that Găbița's claim that her pregnancy was in its second or third month was a lie, and that it has been at least four months. This changes the procedure and also adds the risk of a murder charge. While the two women were certain that they would pay no more than 3,000 lei for the abortion, it slowly becomes clear that Bebe expects both women to have sex with him. Desperate and distressed, Otilia has sex with Bebe, as does Găbița. Bebe then performs the abortion by injecting a probe and an unnamed fluid into Găbița's uterus and leaves Otilia instructions on how to dispose of the fetus when it comes out. Otilia is exasperated by Găbița's lies but continues to help and care for her. Otilia leaves Găbița at the Tineretului to attend Adi's mother's birthday party. She is still disturbed but stays and has dinner with Adi's mother's friends, who are mostly doctors. They converse about trivial matters while Otilia and Adi remain silent. After Otilia accepts a cigarette in front of Adi's parents, one of the guests starts talking about lost values and respect for elders. Adi and Otilia retreat to his room, where she tells him about Găbița's abortion. They begin debating what would happen if it were Otilia who was pregnant, as Adi is opposed to abortion. After the argument, Otilia calls Găbița from Adi's house. Găbița does not answer, so Otilia decides to return to the hotel. When Otilia enters the hotel room, Găbița is lying on the bed, and she tells Otilia that the fetus has been expelled and is in the bathroom. Otilia wraps the fetus with some towels and puts it in a bag, while Găbița asks her to bury it. Otilia walks outside, finally climbing to the top of a building, as Mr. Bebe had suggested, and drops the bag in a trash chute. She returns to the Tineretului and finds Găbița sitting in its restaurant. Otilia sits and tells Găbița that they are never going to talk about the episode again. Otilia stares blankly at Găbița.

London gangster George Thomason and his right-hand man, Ken Pile, an animal lover with a stutter, plan a jewel heist. They bring in two Americans: con artist Wanda Gershwitz and weapons expert Otto West, a mean-spirited Anglophobe. Wanda and Otto are lovers, but they hide this from George and Ken, pretending to be siblings, so Wanda can work her charms on them. The heist is successful, and the gang escapes with a large sum in diamonds that they hide in a safe in an old workshop. Soon after, Wanda and Otto betray George to the police, and he is arrested. They return to collect the diamonds, with Wanda planning to double-cross Otto as well, but find that George has moved them. In Ken's fish tank, Wanda discovers the key to the safe deposit box containing the diamonds and hides it in her pendant. Wanda decides to seduce George's barrister, Archie Leach, so he can persuade George to plead guilty and give up the location of the diamonds. Archie is in a loveless marriage and falls for Wanda; Otto is jealous, and his interference causes Wanda and Archie's liaisons to go disastrously wrong. Wanda accidentally leaves her pendant at Archie's house, and Archie's wife, Wendy, mistakes it as a gift for her. At Wanda's insistence, Archie recovers the pendant by staging a burglary. Eventually, Archie, feeling guilty, ends the affair. George asks Ken to kill Mrs Coady, the Crown 's only eyewitness. To his dismay, Ken accidentally kills her three dogs by means of a series of staged accidents, but ultimately succeeds in his aim when she dies of a heart attack. Wanda and Otto want George to remain in jail, but with no witness, he seems set to get off. At his trial, defence witness Wanda unexpectedly gives evidence against him. When Archie, stunned, flubs his cross-examination and calls her "darling", Wendy realises that Archie has had an affair and decides to divorce him. Otto tries to force Ken to reveal the location of the diamonds by eating his pet fish, leaving Ken's favourite, named Wanda, until last. Ken reveals that the diamonds are at a hotel near Heathrow Airport. With his career and marriage over, Archie resolves to cut his losses, steal the loot, and flee to South America. Promised less jail time, George tells Archie that Ken knows where the diamonds are. Archie sees Wanda fleeing the courthouse, pulls her into his car, and races to Ken's flat. As Archie runs into the building, Otto steals his car, taking Wanda with him. Ken and Archie give chase. Otto and Wanda recover the diamonds, but Wanda double-crosses him and leaves him unconscious in a broom cupboard. Recovering, Otto shoots his way out of the cupboard and is confronted by Archie. Otto is about to kill him, but Archie stalls him by taunting Otto about American failures such as the Vietnam War. Ken arrives driving a steamroller, seeking vengeance for the fish; Otto, who has stepped in wet concrete and cannot move, is run over but survives. Archie and Wanda board the plane, and Otto, clinging to the window outside, curses them until he is blown off during takeoff.

In AD 391, Alexandria is part of the Roman Empire, and Greek philosopher Hypatia is a teacher at the Platonic school, where future leaders are educated. Hypatia is the daughter of Theon, the director of the Musaeum of Alexandria. Hypatia, her father's slave, Davus, and two of her pupils, Orestes and Synesius, are immersed in the changing political and social landscape. Orestes tries to woo Hypatia with music, but she rejects Orestes's love by showing him her menstrual rags, because she prefers to devote herself to science. Davus assists Hypatia in her classes and is interested in science. He is also secretly in love with her. Meanwhile, social unrest begins challenging the Roman rule of the city as Pagans and Christians come into conflict. When the Christians start verbally insulting the statues of the pagan gods, the pagans, including Orestes and Theon, ambush the Christians. However, in the ensuing battle, the pagans unexpectedly find themselves outnumbered by a large Christian mob. Theon is gravely injured, and Hypatia and the pagans take refuge in the Library of the Serapeum. The Christian siege of the library ends when an envoy of the Roman Emperor Theodosius I declares that the pagans are pardoned, but the Christians shall be allowed to take possession of the library. Hypatia and the pagans flee while trying to save the most important scrolls before the Christians overtake the library and destroy its contents. Davus chooses to join the Christian forces. He later returns with a gladius and sexually assaults Hypatia, but he begins to sob and offers his sword to her. However, she removes his slave collar and tells him that he is free. Several years later, Orestes, now converted to Christianity, is prefect (Roman state official serving as governor) of Egypt. Hypatia continues to investigate the motions of the Sun, the Moon, the five known "wanderers" (planets), and the stars. Some Christians ridicule the thinking that the Earth is a sphere by arguing that people far from the top would fall off the Earth. When they ask Davus what his opinion is, he avoids conflict by saying that only God knows these things. Hypatia also investigates the heliocentric model of the Solar System proposed by Aristarchus of Samos by having an object dropped from the mast of a moving ship, which demonstrates that a possible motion of the Earth would not affect the motion, relative to Earth, of a falling object on Earth. However, due to religious objections against heliocentrism, the Christians have now forbidden Hypatia to teach at the school. The Christians and the Jews come into violent conflict. The leader of the Christians, Cyril, views Hypatia as having too much influence over Orestes and stages a public ceremony intended to force Orestes to subjugate her. Hypatia's former pupil, Synesius, now the Bishop of Cyrene, comes to her rescue as a religious authority counterweight but says he cannot help her unless she accepts Christianity; she refuses. Hypatia theorizes that the Earth orbits around the Sun in an elliptical orbit, not a circular orbit, with the Sun at one of the foci. Cyril convinces a mob of Christians that Hypatia is a witch, and they vow to kill her. Davus tries to warn Hypatia, but she is captured. They strip Hypatia and are about to skin her alive until Davus persuades the mob otherwise, and they decide to stone her instead. When the mob goes outside to collect stones, Davus suffocates her to spare her the pain of being stoned and tells the mob that she fainted. Davus leaves as they begin to stone her.

A Kurdish family is trying to survive after the death of its parents. Ayoub, the eldest boy in the family, becomes the head of the household and must do whatever work available to survive. Madi, Ayoub's handicapped brother, is in need of surgery. Ayoub goes to great lengths to collect money for the surgery. He becomes a kolbar and smuggles truck tires with a group of Kurdish villagers near the Iran-Iraq border. Ayoub ultimately falls short of his intended goal and his uncle decides to marry off his sister in return for the groom's family financing Madi's surgery on the Iraqi side of the border. When they arrive the mother of the groom refuses to accept Madi and agrees to give Ayoub and his uncle a mule as compensation. Ayoub decides to take the mule to Iraq, where it is worth more, and sell it to pay for his brother's surgery. Some smugglers let him come along with him. They use mules to carry goods and feed them whisky, allowing them to better survive the harsh mountain winter. However, they are ambushed while heading to the border, and the mules are too drunk to carry on. Ayoub narrowly manages to escape, and the last shot is of him and his brother crossing the border.