Pilot David Randall is paid to fly top-secret photographs from South African astronomer Dr. Emery Bronson to Dr. Cole Hendron in the United States. Hendron, with the assistance of his daughter Joyce, confirms their worst fears: Bronson has discovered a rogue star named Bellus that is on a collision course with Earth.
At the close of the 20th century, all of the Earth's kaiju have been collected by the United Nations Science Committee and confined in an area known as Monsterland, located in the Ogasawara island chain. A special control center is constructed underneath the island to ensure that the monsters stay secure, and to serve as a research facility to study them.
The Stooges are TV actors who are trying to sell ideas for their animated television show The Three Stooges Scrapbook. Unfortunately, their producer does not like anything. He gives the boys ten days to come up with a gimmick or their show will be canceled. In the meantime the Stooges lose their accommodation when they are caught cooking in their room because Curly-Joe turned up the TV-disguised refrigerator way too loud. The only affordable accommodation that will allow cooking is found in an advertisement in a newspaper. The home belongs to Professor Danforth (Emil Sitka) and it resembles a castle.
During an 1864 battle of the American Civil War, a lone Union soldier, Captain Lee Briggs (Bradley Horne), is dispatched on a mission to investigate a mysterious object reported to Union forces. He leaves to venture on the mission.
Flesh (Vince Murdocco) is kidnapped by cheerleaders from a world known only as The Strange Planet, after the men on their planet are rendered impotent thanks to the villain known only as the Evil Presence (William Dennis Hunt). The Evil Presence, who is in an unhappy relationship with Queen Frigid (Maureen Webb), soon learns of Flesh's arrival on the planet, and wishes to transfer Flesh's penis to himself, in order to make up for his own poor endowment.
Orville (Lou Costello) is the oldest orphan at the Hideaway Orphans Home. He accidentally winds up inside a truck heading to a top-secret laboratory, where he is placed under the guidance of lab worker Lester (Bud Abbott) to help load supplies onto a rocket ship. While on board with Lester, Orville hits the ignition button and the rocket blasts off, flying across the country to New Orleans, where Mardi Gras is in progress. They exit the ship and witness "hideous creatures", which are actually costumed celebrants, and conclude that they have landed on Mars.
For the plot of the film-within-the-film, see This Island Earth
The film opens with mad scientist Dr. Clayton Forrester, working from an underground laboratory, explaining the premise of the film (and associated TV series). Mike Nelson and the robots Crow T. Robot, and Tom Servo, along with Gypsy, are aboard the Satellite of Love high in Earth's orbit, when Dr. Forrester forces them to watch the film This Island Earth to break their wills; as per the television show, Mike, Crow, and Tom make fun of the movie as it airs.
Mankind has achieved space flight capability and built "The Wheel" space station in orbit 1,075 miles above Earth. It is commanded by its designer, Colonel Samuel T. Merritt (Walter Brooke). His son, Captain Barney (Eric Fleming), having been aboard for a year, wants to return to Earth.
Distinguished Professor Gordon (John Hoyt) explains that Earth is being tormented by periodic "sex rays" which send people into a sexual frenzy. When one of the rays hits the Ford Tri-Motor passenger aircraft carrying Flesh Gordon (Jason Williams) and Dale Ardor (Suzanne Fields), the pilots abandon the controls and everyone aboard has manic sex. When they finish, Flesh and Dale escape the imminent crash by parachute. They land near the workshop of Flexi Jerkoff (Joseph Hudgins), who has a plan to stop the sex rays at their source.
U. S. Navy Cmdr. Charles "Chuck" Prescott (Thompson) is not sure if his brother, Lt. Dan Prescott (Edwards), is the right choice for piloting the rocket powered Y-13 to very high altitude. Capt. Ben Richards (Ayres) of the Air Force Space Command insists that Dan is their best pilot, even though when piloting the Y-12 into the ionosphere, he began experiencing flight difficulties. Upon landing, Dan broke flight regulations by going to see his girlfriend (Landi), rather than immediately filing his flight report. Despite these concerns, Capt. Richards insists that Dan pilot the Y-13 after a thorough check-out and briefing by Dr. Paul von Essen ([Jaffe).
Fictional television station WIDB-TV (channel 8) experiences problems with its late-night airing of science-fiction classic Amazon Women on the Moon, a 1950s B movie in which Queen Lara (Sybil Danning) and Captain Nelson (Steve Forrest) battle exploding volcanoes and man-eating spiders on the moon. Waiting for the film to resume, an unseen viewer begins channel surfing—simulated by bursts of white noise—through late night cable, with the various segments and sketches of the film representing the programming found on different channels. The viewer intermittently returns to channel 8, where Amazon Women continues to resume airing before faltering once more.
2047. Vingt neuf ans ont passé depuis l'affrontement nucléaire entre les Terriens et les nazis de la lune. Neomenia, l’ancienne base lunaire des nazis, est devenue le dernier refuge de l’Humanité, car la Terre a été dévastée par le conflit. Cependant, ses entrailles cachent une puissance qui pourrait sauver les derniers humains … ou les détruire définitivement. Face à la menace, quelques réfugiés de la Lune vont se rendre au centre de la Terre. Ils y affronteront une race reptilienne extraterrestre.
Marshall Richard "Dick" Dix, a special detective, saves a fast food chain restaurant from a terrorist hostage situation, much to the displeasure of the police chief. He drives away, and back to the police station, where he meets his boss, who is with a police worker, Cassandra Menage. She retells her experience of the cloning of the President of the United States of America, Bill Clinton, who remains unnamed throughout the film. Dix is sent to the cloning facility, a moon base called Vegan. Dix causes a mayhem on the way there. He reaches Vegan, and is met by Lt. Bradford Shitzu at the security check. On the way to meet the main suspect in the cloning, Dr. Griffin Pratt, Dix experiences strange happenings throughout the colony involving certain Aliens who live there. During a very strange incident involving an Alien about to explode, Dix meets Capt. Valentino DiPasquale, with whom Dix will share his quarters. Dix and Shitzu get to Dr. Pratt's quarters, and talk to him. Shitzu leaves, and Pratt takes Dix on a tour of his cloning facility.