Skeletor and his latest allies, the tribal-like Torgs, are trying to awaken Mulkram, a giant, diabolical monster who was frozen by the Elders centuries ago to stop his reign of terror. He-Man, Teela, Man-At-Arms, Orko and Ram Man are in the city of Avion for the annual ceremony where Stratos presents the magical Staff of Avion to his people, but just as the ceremony is about to begin, the Torgs attack, capturing Stratos and the staff. Skeletor intends to use the staff's amazing powers to awaken Mulkram, and to use the mighty creature to enter Castle Grayskull...

Skeletor has gained control of the Cosmic Comet above Eternia, and intends to use it to blow open the jaw bridge of Grayskull. He-Man, Teela, Man-At-Arms, The Sorceress and Orko set out to stop Skeletor's scheme, with the help of Zagraz, a wizard with power over comets.

Skeletor erases He-Man's memory and teleports him to a far-off world called Draenos, which has been rendered barren and desolate by pollution. Cringer, Ram Man and Orko travel to the alien world to rescue Eternia's hero.

An evil wizard called Tauron casts a spell on Orko's Uncle Montork and his pet Gark, turns them evil and sets them on Grayskull!

Zodac comes to Grayskull and tells The Sorceress that Eternia is in great danger as Skeletor is searching for the Starseed, the single most powerful object in the universe- a small chunk of cosmic matter left over from the big bang, which can turn its holder's thoughts into reality. The Sorceress summons He-Man, and together with Battle Cat and Orko, he sets off on a race to reach the Starseed before Skeletor does. But given that the Starseed is able to give anyone all the power that they want, is even He-Man strong enough to resist being corrupted by its power?

A fierce electrical storm brings electronoid Aramesh – a robot made of pure energy – to Eternia from Orko's dimension. He is hunting for Orko, who years ago was entrusted to guard a powerful magical sphere. Skeletor oversees Aramesh's arrival and decides that he could use him to his advantage...

A spacefaring gladiator called the Game Master lands on Eternia, intending to capture He-Man to make him fight for his amusement. But when he sends his minions out to find He-Man, he is in the form of Adam and so He-Man is nowhere to be found. So instead they capture Teela- but they also take Adam's Power Sword, meaning he is faced with the task of rescuing Teela as Adam!

A chess-playing nobleman called Lord Todd, from a far-off land, visits Palace Eternia and instantly charms and astounds the Royal Family with the wonderful gifts he provides them, and his incredible skill at chess. To repay King Randor for allowing him to visit, he offers to take Teela on a tour of his own home- the far-off Castle Star. The two of them depart together. However, things turn disturbing when Man-At-Arms is called to Grayskull by The Sorceress, who tells him that a great evil has arrived on Eternia from another dimension... and it has taken its base nowhere other than Castle Star.....

Stratos is exiled from Avion after being accused of sabotaging the kingdom's defense shield. During his next attack, Skeletor manages to steal the Egg of Avion and hides it in the Demon Zone with his ally Whiplash.

Man-At-Arms has managed to make contact with a peaceful alien being called Om, hovering above Eternia. When Om is being welcomed by the people of Eternos, Skeletor invades the city with General Tataran and the Goblin Army. A fierce battle follows, and Om is confused by the way the two sides fight against one another, as his race knows no violence. So to see which side is wiser and stronger, Om selects He-Man from the side of good, and Skeletor from the side of evil, and pits them against one another in a fight to the finish.

As Prince Adam and Teela attempt to fix a broken-down Attak Trak in the desert, Orko stumbles upon the wizard Kothos, who was transformed into a sand slug by Evil-Lyn in the earlier episode "The Witch and the Warrior". He turns him back to his true form, but has made a mistake as Kothos captures the heroes and offers them to Skeletor in return for his second-in-command, Evil-Lyn, upon whom Kothos is determined to enact revenge.

Prince Adam finds his work as He-Man is tiring him out, and Teela is getting frustrated with Adam's apparent laziness, unaware of the real reason for it. After a heated argument between the two of them, Teela decides to make up for it by making Adam train in a fun way, by following her across an obstacle course with a tracking device. Teela runs way ahead of Adam, but runs headfirst into danger as she slips over the edge of Castle Grayskull's abyss and falls down into its bottomless depths. When they realise the possibly fatal situation Teela is in, Adam (as He-Man), Man-At-Arms and The Sorceress must do their best to rescue her before it's too late.

A small agricultural village is invaded by Space Pirates. When Adam, Teela, Orko and Cringer investigate the village, the Space Pirates steal Adam's sword, leaving him unable to become He-Man. So Adam must take the leading role in his regular identity and convince the villagers to fight back against the Space Pirates, while Cringer sets out to recover the sword.

An evil dragon called Morning Star hopes to resurrect the age-old war between the dragons and humans on Eternia. He extinguishes the Dragon fire, that powers Granamyr's kingdom, and blames it on the humans. War is declared between the humans and dragons, and He-Man is sent on a mission to recover the dragon fire and put and end to the war.

Man-At-Arms is testing out a new duplicating machine, which can make a replica of any solid object. However, the machine is not yet perfect and so its replicas come out being half the size of the original objects. But Skeletor steals the machine, and he uses it to create a whole army of miniature Skeletors to do his bidding... and before long, the palace is overrun with Skeletors!

Prince Adam, Melaktha and Moss Man set sail on an archaeological expedition to the lost island continent of Avathar. When exploring the ancient ruins of the island they come across its legendary mirror, which holds all the greatest knowledge within its glass. They load the mirror onto the ship for their return journey, but its safety is threatened by a disguised Trap Jaw spying on them, and a storm at sea.