Dr. Brilliant and his son Buttons are kidnapped by Professor Envee and forced to work on a duplicate version of Gigantor. Then Envee ties Buttons to its leg and sends it into battle…against Gigantor!
The Keenymeanies have built hundreds of Gigantors to launch them against the planet Snork. Snork's only defense - a badly outnumbered Gigantor, Jimmy and Dick Strong.
When Gigantor takes off by himself without Jimmy at the control, then refuses to obey and crashes into the Boopadoop Embassy, he winds up in chains! What's gone wrong with the big guy?
A master-thief, The Gypsy, sends a fire-breathing mouse robot into the Von Money Estate to steal half an ancient treasure map. Dick Strong joins The Gypsy's gang in a desperate attempt to bring him in.
Ambassador Scamp threatens to blow up a passenger plane unless he's given $1 million. Then he threatens to blow up Big Beaver Dam unless he gets a billion, and Gigantor must be the one who delivers it!
It's the First World Robot Olympics, held in New York. First price, $1 million and a gold trophy. Taurus and Bulba, the favorite, and Gigantor, go head to head until Maxwell Schmoe kidnaps Gigantor!
When the notorious pirate Rapscallion and his crew steal a whaling fleet's money, Gigantor is sent to bring them in. But Jimmy and his giant friend are helpless against Rapscallion's latest weapons.
The International Pirate gang is back in operation. This time, their leader is Rascal Rogue and he's built the largest atomic submarine in the world. Has Gigantor met his match?
The Gypsy is back and this time he manages to unite two pieces of a secret Eskimo map. Now the untold wealth buried deep within Mount Blubber will be his.
Invaders from the planet Magnapus plan to conquer Earth. Able to take human shape at will, one of them has been working as Dr. Brilliant's assistant.
Magnaman is back and he's under the control of Muggs Muggler and his gang, who know his secret code. Only Gigantor can stop them now, but it'll be robot against robot in a duel to the finish.
Dr. Buzz Bugaboo is kidnapped by Brany Mantis and forced to turn over his formula for making huge insects. The big bugs are then unleashed on the city, in numbers too gigantic for even Gigantor to stop.
General Shark has a new secret weapon - termites that eat steel and concrete. Now, no city is safe from a Shark attack. Can Gigantor exterminate the growing problem?
As a reward for rescuing him from the fires of a volcano, a powerful Firebird makes Swami Rivers the most powerful man on Earth. Now only Gigantor can put out his fire.
A robot factory run by a man named Crank unleashes Magnaman, a super robot who's been programmed to destroy all of man's masterpieces, starting with the Eiffel Tower!
Gigantor is sent deep into the ocean to search for a sunken island and buried treasure. Instead, he finds the evil Thermal Updraft, whose hideout is guarded by the unbeatable Albatross robot!
Escaped convict Goldy Brix is attacking luxury liners from his underwater base and using his own giant robot, Blastro. When Blastro disables Gigantor, it's anybody's game!
At Skull Duggery Prison, Goldy Brix is locked up with the monster Big Fang. Big Mistake. They break loose and with help from Professor Stinger's String Ray robots, they can't be stopped.
No country will buy oil from poor Morabia. Rebels from neighboring Togaland have frightened all the customers away by setting oil fires. Can Gigantor take the heat and make everything cool again?
When scientists from the Atomic Factory are kidnapped by a giant whale, Gigantor dives into the sea to see what's going down. But the whale is actually a robot submarine from an undersea city!
Professor Stinger is back and this time he's got Big Fang's robot brother Irontron, who's been built for one purpose only - to defeat Gigantor and jimmy Sparks once and for all!
Dr. Nutzen Boltz convinces Brainy, the robot with a dialectronic brain, to let him study his brain. In exchange, he will build a robot for Brainy that can destroy Gigantor!
The evil Scrag and his henchman Sleek have been building a top secret weapon that uses a Tesla coil to generate lightning - just what they need to get rid of Gigantor for good!
Mr. Skee Matic kidnaps Jimmy and takes him to his secret headquarters where he shows him his robot collection - the largest in the world. Among them, his newest acquisition, Gigantor!
Captain Danger has built two gigantic dinosaur robots in his undersea base and launches an attack on Dr. Brilliant's laboratory while Gigantor is being repaired. Could this be the end?