Dr. Roger Girard is a rich scientist conducting experiments on head transplantation. His caretaker has a son, Danny, who, although fully grown, has the mind of child. One day an escaped psycho-killer invades Girard's home, killing Danny's father before being gunned down himself. With the maniac dying and Danny deeply unsettled by his father's death, Dr. Girard decides to take the final step and transplant the killer's head onto Danny's body.
Earth is invaded by an interstellar terrorist group, Big Fire (the Gargoyle Gang in the American version), led by Emperor Guillotine who spends most of his time in a multicolored space ship hidden at the bottom of Earth's ocean, from which he issues his orders. Big Fire is capturing scientists to create an army of monsters to conquer Earth. A boy named Daisaku Kusama (Johnny Sokko in the American version) and a young Unicorn agent named Jūrō Minami (Jerry Mano in the American version) are shipwrecked on an island after being attacked by a sea monster and subsequently captured by Big Fire. They flee to where a Pharaoh-like giant robot is being built by captive scientist Lucius Guardian, who gives Daisaku and Jūrō its control device. Guardian helps them escape before he is shot to death; before he dies, he triggers an atomic bomb which destroys the base. The radiation activates the robot, which now obeys only Daisaku.
In the hazy aftermath of World War III, the fallout from a 'nuclear misunderstanding' is producing strange mutations amongst the survivors, and the noble Lord Fortnum finds himself transforming into a bed sitting room.
Two young boys sneak aboard a spaceship and find themselves whisked away to the mysterious planet Terra. There, they encounter Gamera's old foe Gyaos and two female aliens with a taste for human brains. Gamera must save the children and battle the new monster Guiron, whose entire body is a deadly living weapon.
The last seven survivors of a nuclear war barricade themselves against the outside world. Beyond a dense mist, other survivors, radiated and mutant, grow hungry.
Tommy Kirk leads his fellow Martians to Earth on an interplanetary quest for females. Kirk proves that Martians have impeccable taste when one of his first conquests turns out to be sexy scientist Yvonne Craig.
The International Rescue team is faced with one of its toughest challenges yet, as the revolutionary lighter-than-air craft Skyship One is hijacked while on her maiden voyage around the world. Against backdrops including the Statue of Liberty and the Sphinx, Lady Penelope, Parker, Alan and Tin-Tin fight the hijackers from on-board, while the rest of the team tries to stop the airship crashing.
As alien invaders plot to conquer the Earth, two Boy Scouts steal a mini-submarine and discover Gamera in their midst. Transported to the alien's spaceship, the Scouts are menaced by the evil inhabitants, including Viras, a squid-like monster that grows to colossal size to battle Gamera.
While searching for oil in the deadly swamplands of the Florida Everglades, members of a geological expedition meet an insane doctor who is working on an experiment to create a creature that is part man and part alligator.
A secret agent possesses a ring that makes him invisible for a short time, once every 10 hours. He is in pursuit of an evil criminal mastermind but, at the same time, must evade an enemy agent who also wants the ring.
The scheming mad scientist Dr. Goldfoot (Vincent Price) plots another mad scheme to take over the world by killing off the major military leaders of every country; to that end, he creates in his secret lab a bevy of bodacious girl bombs; full-length, life-size robots that explode when embraced.
While covering a test of guided torpedoes, two reporters believe they see what appears to be a strange-looking swimming creature. They investigate the matter further and discover that there is a race of fish-men living under the sea. The fish-men capture the pair and keep them prisoner in their underwater city.
In this campy spy movie spoof Dr. Goldfoot (Vincent Price) has invented an army of bikini-clad robots who are programmed to seek out wealthy men and charm them into signing over their assets. Secret agent Craig Gamble (Frankie Avalon) and millionaire Todd Armstrong set out to foil his fiendish plot.
A young man visits his fiancé's estate to discover that her wheelchair-bound scientist father has discovered a meteorite that emits mutating radiation rays that have turned the plants in his greenhouse to giants. When his own wife falls victim to this mysterious power, the old man takes it upon himself to destroy the glowing object with disastrous results.