In 2010, three friends are miserable with their lives: Adam Yates (John Cusack) has been dumped by yet another girlfriend, and his geeky 20-year-old nephew Jacob (Clark Duke) lives in his basement, playing Second Life, with no idea who his father is. Lou Dorchen (Rob Corddry) is a party animal way past his prime. Nick Webber-Agnew (Craig Robinson) has a dead-end job at a dog spa and an unfaithful and controlling wife named Courtney (Kellee Stewart). Lou almost dies from carbon monoxide poisoning in what his friends think is a suicide attempt. Adam and Nick sympathetically take him and Jacob to the site of some of their most memorable weekends, the Kodiak Valley Ski Resort. Upon arrival at the resort, they see that Kodiak Valley has fallen on hard times as well. They are shown to their room by a hostile one-armed bellhop named Phil Wedmaier (Crispin Glover). During a night of heavy drinking in a hot tub, they spill a can of an illegal Russian energy drink called "Chernobly" on the hot tub's controls. The next day, they wake up in 1986. They see each other as their normal age, but in their reflections and to other people, they appear as they did in 1986, except Jacob, who was not yet born. They arrive during "Winterfest '86," the weekend when Poison played to a huge crowd at the then-thriving Kodiak Resort.
On the day of her wedding to news weatherman Derek Dietl, Susan Murphy is struck by a meteorite and its energy causes her to suddenly grow over fifty feet in height during the ceremony. She is tranquilized and awakens in a top secret government facility that houses monsters without human knowledge. She meets the warden W.R. Monger, and fellow inmates: Dr. Cockroach P.H.D., a mad scientist who became half cockroach after an experiment; B.O.B. (Benzoate Ostylezene Bicarbonate), a brainless, living mass of goo as a result of a food flavoring mutation; Insectosaurus, a mutated bug standing at over 300 feet in height, and The Missing Link, a prehistoric fish man who was thawed from deep ice; and Susan herself has been renamed to Ginormica. Meanwhile, in deep space, an alien named Gallaxhar is alerted to the presence of quantonium; a powerful energy source on Earth, and he sends a probe to retrieve it. After the probe crash lands on Earth, the president attempts to make first contact with it by playing a keyboard version of Axel F, but it begins to rampage toward San Francisco.
A future post-apocalyptic world is ruled by the good-looking people. A terrorist group of disabled people, who see themselves as mutants, take arms against their oppressors. They plan to rid the world of "beautiful people" and superficiality. They are very inept at what they do and mistrust one another. They assassinate body builders, massacre an aerobics class on live TV and blow up a sperm bank as part of their violent campaign.
Dr. Stanislaus Pyckle, (a play of the actor's name, Stan Laurel), successfully separates the good and evil of man's nature with the use of a powerful drug -- "Dr. Pyckle's 58th Variety", a spoof of "Heinz's 57". Transforming into the personality of Mr. Pride (again Laurel), he terrorizes the town with unspeakable acts including stealing a boy’s ice cream, cheating at marbles, and popping a bag behind a lady pedestrian. The townspeople track him down where Mr. Pride locks himself in the laboratory and transforms back at Dr. Pyckle. The doctor assures the townspeople that he hasn't seen the "fiend" they were after. While he talks, the drug used for the transformation spills in the plate of food of the doctor's dog. Dr. Pyckle confronts the fiendish dog when he locks the door and the townspeople leave. But once again, Mr. Pride emerges and brings havoc to the town, and again is chased down by the townspeople. He enters the lab and transforms back into Pyckle, and again assures the townspeople he hasn't seen the fiend. His assistant (Julie Leonard) begs the doctor to open and comfort him, but he transforms back into Mr. Pride. He opens the door to the assistant and locks it again. She screams seeing Pride and the townspeople hurry back, before the assistant can knock Pride down.
The film opens in the utopian future that results from the music of Bill (Alex Winter) and Ted (Keanu Reeves). Chuck De Nomolos (Joss Ackland), who detests this society, steals one of the time-traveling phone booths and sends two robots modeled after Bill and Ted to the late 20th century, with the intent to prevent Bill and Ted from winning the San Dimas Battle of the Bands. Rufus (George Carlin) attempts to stop De Nomolos but becomes lost in the circuits of time.
The Earth is passing through the tail of a comet, an event which has not occurred in 65 million years, the last time coinciding with the extinction event that wiped out the dinosaurs. On the night of the comet's passage (which takes place eleven days before Christmas), large crowds gather outside to watch and celebrate.
The Institute for Advanced Concepts, a group of scientists with an unlimited budget and a propensity for elaborate pranks, brainwash a psychology professor named Simon Mendelssohn who was abandoned at birth and manage to convince him, and the rest of the world, that he is of extraterrestrial origin. Simon escapes and attempts to reform American culture by overriding TV signals with a high-powered TV transmitter, becoming a national celebrity in the process.
Skye (Brooke Shields) is interviewing beloved former child star Ricky Coogin (Alex Winter). Rather bluntly, Skye asks how Ricky so quickly went from one of America's sweethearts to a name that makes children scream in terror.
Five years after Agent K's retirement, Agent J (Will Smith) is now a top operative for the MIB, the New York City-based agency that secretly monitors and regulates extraterrestrials' activity on Earth. J has no permanent partner since K resigned and Agent L returned to work in a morgue. Subsequent partners have not lived up to J's standards, so he neuralyzes them back to civilian status.
At Medfield College, science buff Dexter Riley and his friends, including Richard Schuyler and Debbie Dawson, eavesdrop via a hidden walkie-talkie on a board meeting led by Dean Eugene Higgins, discussing the small college's continuing precarious finances. Later that afternoon, Professor Lufkin shows Higgins around the science lab where Dexter is working on an experiment with invisibility and another student, Druffle, explores the flight of bumblebees. That night, unknown to anyone, during a powerful thunderstorm, the roof of the lab is struck by lightning, sending a current of electricity down a metal beam and through Dexter's complex experiment components. The next day, as Dexter examines his burnt equipment with dismay, Higgins meets with A. J. Arno, a recently released prisoner, who had also purchased Medfield's mortgage. When Dexter accidentally drops one half of his glasses into a container of his experimental formula, it appears as if the substance destroys them, but upon closer examination, Dexter realizes the frames are merely partially invisible. After several excited tests, Dexter boldly places his fingers in the liquid and they disappear. Schuyler and Debbie arrive and are horrified to see Dexter with a partial hand, but Dexter insists Schuyler test the substance as well, admitting only afterward that he does not yet have an antidote.
Lee Chak-Sing (Stephen Chow) is a rich kid living in Hawaii. He's arrogant and fond of playing mean tricks on everyone around him. His life changes when he meets Chung-Chung (Gigi Leung), a young woman whom he declares is very ugly.
The film begins with graduate student Teri MacDonald (Helen Hunt) and her work training a chimpanzee named Virgil to use American Sign Language. When her research grant is not renewed, Virgil is taken away. Teri is told that Virgil will be sent to a zoo. Instead, he is taken to an Air Force base to be used in a top-secret research project involving platforms designed to simulate the operation of aircraft.
Three thousand years ago, an Aztec warlord named Yaotl and his four generals discover a portal opening into a parallel universe which is said to have great power. Yaotl becomes immortal but at a high price, as his four generals were turned to stone. The portal releases thirteen immortal monsters that destroy his army as well as his enemies. In the present, the Teenage Mutant Ninja Turtles have grown apart. After defeating the Shredder, Master Splinter has sent Leonardo to Central America for training. Donatello works as an IT specialist, Michelangelo works as a birthday party entertainer called Cowabunga Carl and Raphael works at night as a vigilante nicknamed Nightwatcher. April O'Neil operates a company that locates and acquires relics for collectors with the help of her boyfriend, Casey Jones.
The Great Gonzo has always been identified as a "whatever". But after he begins having disturbing dreams of abandonment and rejection, he begins to realize just how alone he is in the world. One of his nightmares involves him being denied entry onto Noah's Ark by Noah (F. Murray Abraham). The next morning, Gonzo tells Kermit the Frog that he is getting tired of being called a "whatever." After an alien race appears to be trying to send him a message through bowls of cereal, Gonzo realizes that he may not be so alone after all and climbs to the rooftop to start watching the sky. Using a bolt of lightning, Gonzo communicates with a pair of cosmic fish, revealing to him that he is an alien from outer space.
In the near future, the Moon has been colonized and supports a station on its surface. A lunar shuttle known as Mayflower One is being rushed to launch from Houston. The head of the ground crew, The Sarge (Chuck Connors), does not like what is occurring, but he defers to the airline's management.