On July 20, 1969, astronaut Jim Lovell hosts a party, where guests watch on television as Neil Armstrong takes his first steps on the Moon during Apollo 11. After the party, Lovell, who had orbited the Moon on Apollo 8, tells his wife Marilyn that he intends to walk on the Moon's surface.
On May 10, 1998, teenage amateur astronomer Leo Biederman discovers an unusual object near the stars Mizar and Alcor at a star party in Richmond, Virginia with his school's astronomy club. His teacher alerts astronomer Dr. Marcus Wolf, who realizes that the object is a comet on a collision course with Earth. Wolf dies in a car accident before he can alert the world.
In Upstate New York, a waste management firm loads barrels of toxic waste onto trucks, intending to illegally dispose of them. They are shown heading into a tunnel under the Hudson River between Lower Manhattan and Jersey City, New Jersey along with several other commuters, including struggling playwright Maddy Thompson (Amy Brenneman), some young offenders, a vacationing family, an elderly couple, and a mountain climber named Roy Nord (Viggo Mortensen). Meanwhile, a gang of diamond thieves in a stolen car try to escape the NYPD by racing into the tunnel. The gang force their way through the north tube traffic, spilling the diamonds all over the floor of the car. While a female thief tries to retrieve them, she pushes the gas pedal to the floor, causing the driver to lose control, smashing though a security booth and into one of the trucks, killing them instantly. The waste barrels explode, causing the other trucks to explode and setting off a chain reaction. The tunnel entrances cave in, and a devastating fireball sweeps through the tunnel, incinerating thousands of cars and people.
Jay Baruchel arrives in Los Angeles to visit with old friend and fellow actor Seth Rogen, who invites him to attend a housewarming party hosted by James Franco. Jay is uncomfortable being around so many people he hardly knows, so Seth accompanies him to a convenience store for cigarettes.
An earthquake strikes the city of Los Angeles. Mike Roark (Tommy Lee Jones), the head of the city's Office of Emergency Management, insists on coming to work to help out with the crisis, even though he has taken a vacation with his daughter Kelly (Gaby Hoffmann). His associate Emmit Reese (Don Cheadle) notes the quake caused no major damage, but seven utility workers are later burned to death in a storm drain, one escaped and survived but was severely burned on one side of his face at MacArthur Park. As a precaution, Roark tries to halt the subway lines which run parallel to where the deaths took place, but Los Angeles MTA Chairman Stan Olber (John Carroll Lynch) declines, feeling there is no threat to the trains. Against regulations, Roark and a colleague Gator Harris (Michael Rispoli) venture down the storm sewer in the park to investigate. They are nearly burned to death when hot gases suddenly spew out of a crack in the concrete lining and flood the tunnel. Geologist Dr. Amy Barnes (Anne Heche) believes a volcano may be rapidly forming beneath the city with magma flowing underground (similar to the formation of the Mexican volcano Parícutin which emerged and grew tremendously in just one week) but cannot come up with enough evidence for Roark to take action.
Architect Doug Roberts (Newman) returns to San Francisco for the dedication of the Glass Tower, which he designed for owner James Duncan (Holden). At 138 stories (1,800 ft/550 m), it is the world's tallest building. Shortly after his arrival, an electrical short starts an undetected fire on the 81st floor while Roberts accuses the building's electrical engineer, Roger Simmons (Chamberlain), of cutting corners. Simmons insists the building is up to standards.
On the morning of September 11, 2001, four al-Qaeda terrorists Ziad Jarrah, Saeed al-Ghamdi, Ahmed al-Nami, and Ahmed al-Haznawi pray in their respective hotel rooms before arriving at Newark Liberty International Airport. The quartet wait at a gate after getting through security to board San Francisco-bound United 93. After 40 minutes of delay due to traffic the plane takes off, flown by captain Jason Dahl and first officer Leroy Homer, with all four terrorists on board.
A privately owned luxury Boeing 747-100, Stevens' Flight 23, flies invited guests to an estate in Palm Beach, Florida, owned by wealthy philanthropist Philip Stevens, who also owns the jetliner. Valuable artwork from Stevens's private collection is also on board the jetliner, to be eventually displayed in his new museum. Such a collection motivates a group of thieves led by co-pilot Bob Chambers to hijack the aircraft.
Kevin Harrison (Robert Wagner), a corrupt arms dealer, attempts to destroy an American-owned Concorde on its maiden flight after one of the passengers, reporter Maggie Whelan (Susan Blakely), learns of his weapons sales to communist countries during the Cold War.
During a routine flight to Minneapolis, a passenger (Susan Dey) aboard Global Airways Flight 502, a Boeing 707, discovers a bomb threat written on the mirror of one of the first-class bathrooms. A second threat is soon found left on a napkin in a galley. Captain Hank O'Hara (Charlton Heston) takes the cryptic threats seriously and follows the instructions -- "Bomb on plane divert to Anchorage Alaska. No Joke, No Tricks. Death"—by changing course for Alaska. To avoid an explosive decompression if a bomb goes off, he flies at lower altitude, increasing fuel consumption.
Shelby Gilmore (William Holden), who owns a newly constructed hotel on a remote Pacific island, wants desperately to marry his secretary, Kay Kirby (Jacqueline Bisset) and proposes to her under the impression that she'll become his seventh wife. Kay is in love with Hank Anderson (Paul Newman), an oil rigger whose scientists are warning him that a nearby active volcano is about to erupt.
The film tells the story of Dr. Henry Jekyll (Fredric March), a kind English doctor in Victorian London, who is certain that within each man lurks impulses for both good and evil. One evening, Jekyll attends a party at the home of his fiancée Muriel Carew (Rose Hobart), the daughter of Brigadier General Sir Danvers Carew (Halliwell Hobbes). After the other guests have left, Jekyll informs Sir Danvers that, after speaking to Muriel, he wants Carew's permission to push up their wedding date. Sir Danvers sternly refuses Jekyll's request. Later, while walking home with his colleague, Dr. John Lanyon (Holmes Herbert), Jekyll spots a bar singer, Ivy Pearson (Miriam Hopkins), being attacked by a man outside her boarding house. Jekyll drives the man away and carries Ivy up to her room to attend to her. Ivy begins flirting with Jekyll and feigning injury, but Jekyll fights temptation and leaves with Lanyon.
Après plusieurs semaines de pluie torentielle, les habitants soucieux de la sécurité de la petite ville de Brownsville demandent à leur maire d'ouvrir les vannes pour faire sortir le surplus d'eau du barrage mais ce dernier refuse. La construction cède et c'est la panique pour les quelques habitants qui vont devoir faire l'impossible pour survivre.