Adam and Teela visit an ancient castle where an evil Lord and Lady once lived, practising black magic by absorbing energy from the trees, until the trees died and they began a centuries-long sleep in their coffins. As Adam and Teela ride some winged horses, Lady Valtera and Lord Tyran awake from their coffins. Lord Tyran's appearance has been greatly disfigured by his evil ways- so severely that Valtera does not recognise him. When Valtera comes across Adam and captures him to be her slave, Tyran thinks she is more interested in Adam than him and wreaks havoc attempting to gain all the power he can, and capturing Teela along the way.

Skeletor wants to steal the Widgets' Coridite- a powerful mineral substance, out of which He-Man's harness is made. Evil-Lyn devises a cunning scheme to help him; she disguises herself as a young girl lost in the forest, and persuades the Widgets to let her enter their fortress. She then tricks the Widget guard Squinch into letting her enter the private chamber where the Coridite is kept, then she steals the Coridite and takes it to Skeletor! Skeletor plans to use the Coridite to form himself a new chest plate that will make him as powerful as He-Man- can He-Man stop Skeletor's scheme and retrieve the Coridite before his most dangerous foe becomes as powerful as him?

An inventor called Zicran visits the Royal Palace to deliver a Transmutator machine to Man-At-Arms, accompanied by his daughter Ileena, a friend of Teela's. Ileena is vulnerable and lacking in self-confidence, feeling inferior compared to Teela's agility. Meanwhile, an evil sorcerer called Jarvan, who was previously defeated by He-Man and Man-At-Arms, has escaped from the prison mines and has set his sights on the Transmutator. Preying on Ileena's depression, he disguises himself as a kindly old woman and gives Ileena a 'magic potion' that will boost her confidence and strength. But the potion contains a dangerous drug, and Ileena soon finds herself addicted to the drug, and almost causes several serious accidents while under its effects. She also finds herself unwittingly obeying Jarvan's commands, and helps him to obtain the Transmutator! Can the heroic warriors cure Ileena's addiction before she causes more damage to herself and the people around her?

While bored, Orko casts a spell to bring a small, cute creature called Daimar, from a book about the dimension of darkness, to Eternia. But Daimar doesn't stay cute for long- he soon turns into a giant demon and is threatening to overcome Grayskull with his power, which Skeletor is also determined to acquire for himself!

While entertaining the Royal Family with his magic, Orko finds his act interrupted by a strange sorceress called Majestra. Majestra performs a trick in which she appears to make the King vanish then reappear- but in fact, Majestra is really Evil-Lyn in disguise, and has teleported the King to the dungeon and replaced him with a disguised Beast Man! Evil-Lyn has found a magical Shaping Staff which can transform anything into whatever the holder wishes- and under their disguises, Evil-Lyn and Beast Man set about causing havoc around the palace, turning each member of the Royal Family into helpless animals, while Skeletor awaits them at Grayskull with his latest creation- an evil version of He-Man, called Faker!

Orko thinks that everyone has forgotten his birthday, when Man-At-Arms reports word of strange destruction the town of Becilia. He-Man, Teela and Ram Man go to investigate, and find themselves in the middle of a tornado some very curious effects – one of which is He-Man's sword disappearing, as a result of some strange influence somewhere. Meanwhile, Orko, upset at his birthday seemingly being forgotten, heads off to see The Sorceress, only to find that Castle Grayskull is gone! Skeletor has managed to harness a White Hole, with which he has sucked the castle, with The Sorceress inside it, into a strange reverse dimension, where he is trying to use the backwards laws of the dimension to harness it's powers. He-Man, Battle Cat and (unintentionally) Teela head into the White Hole to try and stop this latest evil attempt...

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!

He-Man's sword is taken by a peaceful race of Rock People who believe the sword gives them power. Fearing that himself and Battle Cat may never be able to become Adam and Cringer again, He-Man must journey to the underground world of the Rock People to recover the sword.

He-Man and Battle Cat rescue a young girl in the jungle from three soldiers, and she tells them she is Princess Raya of the kingdom of Abherran, and the soliders were minions of Queen Valena of Targa, Ahberran's rival kingdom. He-Man journeys back to Ahberran with Raya, hoping to somehow stop the war between the two cities, but on the way He-Man is knocked unconscious by a falling tree and taken prisoner by Valena's soldiers. When he awakes he has lost his memory and has been imprisoned with an arena fighter called Garn, whom Queen Valena has promised freedom if he wins his next fight. He-Man is forced to fight Garn, but his main aim is to regain his memory and free the countless slaves whom Valena is forcing to fight for amusement. And will he regain his memory in time to help Raya return safely to Ahberran, and stop the war?

Adam, Teela and Cringer are exploring the Valley of Power, which contains magical water which imbues anyone who drinks it with great power. But a stranger called Danavas is also in the area, and has stolen the egg of a Mother Rogue. When the baby bird hatches, he makes it drink the water and gain its power, so he can control it for himself. The bird grows to giant size, and soon the Royal Palace is in danger from Danavas' adopted pet!

Negator, an evil character with a love of computers and electronics, sees Man-At-Arms testing out his latest invention, the Beam Ray, in the desert. Impressed, Negator wants the scientist to come and work for him, so that he can use his creations for his own evil purposes. When Man-At-Arms refuses, Negator captures Teela to force him to come to him. As He-Man, Ram Man and Battle Cat search for their missing friends, they are sucked into Negator's underground electronic domain, and Negator sends He-Man and Ram Man into his living electronic "game"...

A villain called Azrog is arrested on Trolla by Uncle Montork, but he flees to Eternia where he joins forces with the witch Spydra. Montork follows him, but ends up imprisoned in Spydra's castle. When He-Man, Battle Cat, Teela and Orko go to rescue Montork, Orko falls under Azrog's spell and becomes evil, and is set against his friends.

Prince Adam tells Man-At-Arms the story of how he, as He-Man, changed the life of Man-E-Faces. In flashback, we see how Man-E was once a bad guy who terrorized the Widgets with his three faces, and how Skeletor tried to recruit him into his forces before He-Man enabled Man-E to see the error of his ways.

Whilst on an archaeological dig, Man-At-Arms and Professor Smallen are taken captive by ancient robots called Zaktons, who were left by the Ancient Ones to guard the ruins of the desert. He-Man and Teela head to the Ancient Ruins to save them, but they also face danger from Trap Jaw, who wants the Zaktons' artifacts for himself.

When on a skiing holiday in the icy regions of Eternia, the Royal Family are captured by an Ice Lord. Orko scares the Ice Lord by pretending he is He-Man (!), and the Ice Lord explains that Skeletor has kidnapped his daughter and will only release her if the Ice Lord delivers the Royal Family to him. Orko convinces the Ice Lord to free Prince Adam (who he calls his 'assistant'), then Adam becomes He-Man and sets off to Snake Mountain with Orko to rescue the Ice Lord's daughter.

When exploring an ancient temple, Prince Adam and He-Man come across the Masks of Power, which conceal the spirits of an ancient evil race. Two power-hungry travellers steal the masks, and their bodies are possessed by the spirits within them. Together they go to Snake Mountain, where they offer Skeletor their services- but Skeletor will only recruit them after they have passed a series of tests, one of which involves recovering the Sword of the Ancients from deep within Snake Mountain.

Evil-Lyn captures Mira, the daughter of the powerful wizard Kor, and frames He-Man and Man-At-Arms for the capture. Kor takes He-Man and Man-At-Arms prisoner, and refuses to listen to their pleas for innocence, planning to unleash a demonic entity called the Crimson Scourge upon them unless they reveal his daughter's whereabouts.

He-Man and Man-At-Arms set sail to investigate the disappearance of some of King Randor's food ships. Sucked beneath the surface by a whirlpool, they find themselves in the underwater city of Aquatica, which has been taken over by Merman. Merman has kidnapped the city's princess, Nahmi, and is controlling the Aquaticans with the Pearl of Power! But he has convinced them that the surface dwellers kidnapped Nahmi, and the Aquaticans have waged war against the people of the surface. Can He-Man help the Aquaticans see the light, and rescue Princess Nahmi before Merman creates more havoc?

Queen Sybilline, apparently once one of the most evil sorceresses in Eternia, has defected to the side of good. She enlists the help of He-Man and his companions in restoring King Danton of the Isle of Tears to the throne, having helped the evil Gorgon to overthrow him. But will they succeed, when Gorgon has recruited Evil-Lyn as his replacement sorceress?

When testing out a teleportation device created by Man-At-Arms, Teela accidentally teleports Man-At-Arms away, and no-one knows where to. Overcome with guilt, believing she has caused a terrible fate for her father, Teela exiles herself to the Wastelands. Meanwhile, Man-At-Arms has been teleported into the clutches of Skeletor, who has imprisoned him, forcing him to make weapons for his own evil crew. He-Man must rescue Man-At-Arms, as well as convincing Teela to forgive herself for her mistake.

He-Man rescues a small girl from danger in the Evergreen Forest, and it turns out that the girl is a magical Starchild- and two tribes in the forest, the Tree People and the Cave People, are fighting for custody of her. He-Man takes the Starchild back to Palace Eternia with him, so the Royal Family can sort out the custody battle.

When he is practising a magic spell, Orko's magic is stolen by a small creature called a Gronk, which teleports to another world. The Sorceress traces Orko's magic to the strange world of Omiros, and He-Man and Orko journey there to recover the magic. On this surreal planet, they find that an evil wizard called Zolt has absorbed Orko's magic and is using it to control Omiros. They must fight Zolt and recover Orko's magic before the portal back to Eternia closes!

Darkdream, an evil being who can control people's dreams, has been freed from the seal in which he was imprisoned, and is now using his powers to once again give the people of Eternia terrible nightmares. With his allies Evil-Lyn and evil magician Trebor, Darkdream plans to bring eternal darkness to Eternia so he can roam it freely and bring it his reign of terror once again...

Prince Adam's cousin, the bratty and snobbish Prince Jeremy, visits the Royal Palace, and quickly starts to annoy everyone with his rudeness and spoilt behavior. When Evil-Lyn and Tri-Clops arrive on the scene, they take advantage of Jeremy's spoiltness to lead him into unwittingly helping them in a scheme to break into Grayskull.....

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...