Somewhere out in the deep space live the Herculoids. Humanoid Zandor, along with his wife Tara and son Dorno, lead a group of unique creatures: Zok the flying dragon, powerful simian Igoo, rhinoceros hybrid Tundro and two protoplasmic wonders named Gloop and Gleep. Together, they use their diverse super strengths to defend their utopian planet against attack from sinister invaders.
After killing two creatures with a treasure chest, pirates bury it on Amzot. When the Herculoids approach, Dorno is captured and held hostage.
Sarko captured Igoo for unknown reasons, attacked Zandor with sleeping gas, and captured Dorno and Tundro as well.
An alien spacecraft hovers over Amzot, dropping mechanical pods onto the planet. Meanwhile, Dorno, Igoo and Gleep, on a mission to get firewood, see the robotic pod creatures as the pods open up and start attacking the trio.
A group of powerful robots, led by a larger robot, attack the Herculoids.
Krokar, leader of the Beaked People, stages an invasion on the Winged Monkeys, purposely letting one escape so he can capture Zandor and rule Amzot.
Sta-Lak flew over Amzot; upon seeing Zandor and Zok, Sta-Lak turned his ship invisible to avoid detection, with the intent of taking Tara prisoner.
After being woken up by a bird, Zandor investigates Marcon and the Mole Men's plans to invade the surface world, saving a condemned prisoner in the process. Meanwhile, other Mole Men are attacking the Herculoids.
Zandor rescues a young boy from a vulture; the Herculoids then take the boy back to his heavily-shadowed home because he can not live in sunlight. The insect-looking creatures attack the Herculoids on their way out.
A group of spider-like creatures kidnap Dorno, then try doing the same with Tara. Gloop saves her while Gleep blows a horn beckoning the Herculoids to action. Zandor briefly frees Dorno with his shield but is soon captured with Dorno. After a stalemate, Zandor calls the Herculoids to action for one concentrated attack.
Zandor was captured by Gorvac, leader of the Android People, and created a giant evil clone of Zandor with plans to create an army of Zandor clones.
Andropon and his robots invade Amzot, where the Herculoids easily defeat them. After Andropon continuously threatens to build replacement robot armies (and Zandor continuously vows to defeat said armies), Andropon pits his top warrior Ogron against Zandor and Zok.
Brotak and his Bubblemen kidnap Zandor and Tara for the purpose of using them as scientific experiments.
Trained machines break Mekkano out of an intergalactic prison, where he vows to destroy the ones who put him in prison: Zandor and the Herculoids.
Torrak shrinks the Herculoids down to microscopic size for the purpose of destroying them with his super-powered microorganisms and then enslaving the galaxy.
After destroying the last wild creature of Kyanite, Neron and his gladiators capture Tundro. Zandor and Zok, followed by the rest of the Herculoids, arrive at the arena to rescue Tundro and fight the gladiators.
The unnamed high priest of Trax kidnaps Tara in order to use her as a sacrifice for the idol Trax, cutting off the Herculoids in their rescue attempt. Can Zandor and Zok, who are miles away, get to Trax in time?
Oton, leader of the Time Creatures, has determined that in order to rule Amzot in the future, he has to change its past, starting with destroying the Herculoids and altering time in his favor.
Gotron and his Raider Apes burn a village in search of gold. The Herculoids come to the villagers' aid.
A terrible wind storm is raging on Amzot. However, Zandor notices that winds on the left side of a canyon are aiming right, while winds travel in the opposite direction on the right side. Zandor and the Herculoids investigate, and discover Konar is destroying Amzot's atmosphere to replace it with his own. Konar sends his henchmen, who are either killed or injured by the Herculoids. As Zandor confronts Konar, Konar brings out the giant Zorbots to take on the Herculoids. Zandor chooses to surrender in order to destroy the wind machine from within and, when successful, battle the Zorbots.
Volton and his Electrode Men fly into a volcanic crater, setting up a dome headquarters to take over Amzot. The Herculoids are easily defeating them until Volton takes Tara and Dorno prisoner. Zandor and the Herculoids have to wait until nightfall, when the Electrode Men's power is weakened.
A lightning storm causes a nest of giant ant eggs to hatch. The giant ants cause havoc and destruction and Zandor and the Herculoids must put an end to them.
A hideous monster emerges from a swamp and goes on a rampage, destroying anything it comes in contact with by its radioactive touch. It eventually traps Dorno and Gleep in a cave, and it is up to Zandor and the rest of the Herculoids to rescue them and defeat the creature.
Amak and the Amatons come to the planet and place control collars on some animals. When their efforts to enslave the Herculoids fail, Amak tries to kill them. Gloop and Gleep save the day by turning Amak's stun turret on him, causing his ship to crash.
Queen Skorra unleashes a mud/lava creature which they eventually defeat, but Skorra plans to force them into exile by sending her drones to capture Gleep, Gloop, Tara, and Dorno. They defend themselves long enough for Zandor and the others to return and drive off the drones. Skorra launches a mega-shield missile and closes the mega-circle to destroy everyone, but Tundro creates a smokescreen while the others make a tunnel to escape and then send Skorra running.
The story starts with Zandor knocked out by the Laser Lancers and the Herculoids coming to the rescue. Magoth and the Lancers send a new wave of attackers which the Herculoids repel, but it is a ploy to take Dorno and Tara hostage. With Gleep's help, they seal off the tunnel the Lancers used to sneak up and repel them once and for all.
The princess Serena of the Sun People arrives on Amzot, being pursued by Darkon of the Faceless People. Darkon wants Serena so he can control her people. The Herculoids successfully drive him off, but not before he captures Tara. Zandor agrees to a trade, but substitutes a berobed Gleep for Serena and they destroy Darkon's palace from the inside.
A ship crash-lands on Amzot with a sole occupant on board. Zandor offers assistance and the passenger turns out to be a Mutoid, a race who can change their appearance to anything. The Mutoids plan to use Amzot as a launching site for their missiles to fool their enemies. Can Zandor and the Herculoids stop them in time?
A meteor crash-lands on Azmot and transforms into a giant crystalline object. Zandor investigates and is attacked by the Crystalites, while Tara and Dorno are captured in crystal cells. Zandor, Gloop, and Gleep steal uniforms, sneak into the fortress and free Dorno and Tara. Gloop and Zok destroy Kryton's ship and he is defeated.
Sta-Lak returns to Amzot seeking vengeance and equipped with robot duplicates of Igoo, Zok, and Tundro. He captures Dorno, Tara and Zandor and the others are forced to go into his volcano lair. The robot duplicates prove no match to the originals, even though the robot Igoo can spin at high speeds and has multiple arms, and the robot Tundro can fly. Sta-Lak enters a bubble and flees into a volcanic lavahole.
The pirate captain and his crew from "The Pirates" return. Using an image transmitter, the captain immobilizes Zandor and the Herculoids and takes Dorno and Tara prisoner. Zok uses his neutralizing eye beams to free them, then Gloop finds the real Dorno and Tara from the transmitted images and the Herculoids launch a new assault. The captain tries to escape, but Gloop blocks his escape missile tube, causing the ship to explode.
Tara is captured by the Reptons, who place her in a mind control device to make her their evil queen. She orders her people to destroy Zandor and the Herculoids, who beat them and go to rescue Tara. The Reptons send the Destructo Bats after them, but they escape, recover Tara, free her from the machine's influence, and destroy the Reptons' underground lair.
While investigating panic among the Monkey People, Zandor confronts a giant spider and is bitten and poisoned. Dorno must go to the six-legged mustachioed Spider People within the Endless Caves with the Herculoids to get the only known antidote. The Spider People capture Dorno to hold him hostage. The Herculoids eventually stage a rescue, get the antidote, and block the Spider People's caves to cover their escape.
Amzot is being bombarded by the planet Luvanuum. Zaygot and his henchmen are trying to destroy Azmot. The Herculoids travel to Luvanuum in a ship captured from Sarco. When they land, their ship is destroyed and they are attacked by winged sentries with deadly laser beams. The Herculoids destroy Zaygot's base and he escapes - they use Zaygot's ship to return to Amzot.
Torrak returns and sends out a giant fly to capture Tara. The Herculoids follow and discover that Torrak's warrior microorganisms are now larger and more formidable, but defeat them anyway.
Zandor and Dorno rescue a man floating in the river who says he is from Gravite Island and tells them that a villain has taken over the island. The Herculoids go to investigate and are attacked by giant gravite creatures. The creatures are being created by Lotak, who wants the village because of its large deposits of gravite. Zok destroys the machine Lotak uses to make his creatures and Lotak is destroyed when his energy ray backfires.
Malak sends his Metal Apes to attack the Sea People. Dorno is shot off of Zok by one of the creatures. Zandor and the Herculoids destroy the Metal Apes. A damaged Metal Ape returns to Malak's headquarters and is followed by the Herculoids. The Herculoids destroy the remaining Metal Apes and Zok causes a steel beam to fall on Malak and his assistant.
