Release date: September 30, 1983
Lady Irena, a childhood friend of Prince Adam, visits the palace of Eternia. While everyone else is excited by her arrival, Orko sees her sharpening a dagger in her room.
Puzzled by what he saw, he entertains the guests at a royal banquet. Orko tries to make a plant grow a flower by playing the flute, but instead shatters King Randor's glass. Irena becomes angry and throws her glass at Orko.
Later, in the corridors of the castle, Orko tells Adam about seeing Irena with a knife. Adam says that the Irena he grew up with hates weapons and violence. Adam transforms into He-Man goes to Castle Grayskull with Battle Cat to investigate.
The Sorceress shows them a vision of Lady Irena playing her harp for the court. The music is bewitching everyone. The Sorceress then shows them a second vision, this one of Lady Irena trapped in a bubble and guarded by Mer-Man. He-Man realizes that Lady Irena has been replaced by an imposter!
He-Man rushes back to the palace and shatters her harp with the power sword. The proximity of the power sword numbs her hand, causing her to drop her dagger and reveal her true form. "Lady Irena" turns into one of Skeletor's demons!
Skeletor, Trap-Jaw, Tri-Klops and Beast Man appear and fight He-Man, Teela, Man-At-Arms, Battle Cat and even King Randor. Skeletor retreats along with his Evil Warriors.
The heroes rush off to find the real Lady Irena. He-Man scares off Mer-Man, but not before he says that the crystal bubble that holds Irena is stronger than He-Man's sword and that she will soon run out of air! He-Man tries, but the power sword isn't able to break the bubble. However, He-Man borrows Orko's flute from Man-At-Arms and uses it to shatter the bubble.
The story ends with Orko entertaining King Randor and his guests by successfully trying to get the plant to grow flowers with his flute while Teela teases Prince Adam about missing all of the excitement.