He-Man and the Masters of the Universe (1983)

S2E60 Bargain with Evil

A wicked monarch from the Shadow Realm has captured a noble sorcerer. In a desperate attempt to rescue him, his daughter strikes a deal to abduct the Star Child, allowing the king to gaze upon her. However, she quickly realizes she has been tricked when the malevolent ruler reneges on their agreement, transporting her, the Star Child, and her protectors to his realm. He plans to coerce the Star Child into unleashing her powers to create a portal to Eternia, enabling his army to invade and conquer.