This comic, the first of the five DC Comics' Masters of the Universe series, introduces Prince Adam as a brawling, womanizing youth and Teela as the newest member of the Royal Guard. Prince Adam is at a tavern with Cringer when a huge man approaches him, picking a fight. Adam readily accepts this challenge, but Teela breaks it up before it gets good. Hearing the cry of the falcon, Adam and Cringer bolt off to the Cave of Power, where they meet with the Sorceress in her snake outfit and become He-Man and Battle Cat. Meanwhile, Skeletor inadvertantly causes a dimensional rift between Earth and Eternia while trying to open Grayskull, and Superman is sucked through. Superman ends up taking on Skeletor and Beast Man until He-Man, Battle Cat, and Man-At-Arms arrive, where Skeletor then puts a spell on Superman to fight with He-Man. Superman barely disables He-Man temporarily, then stops Skeletor. Afterward, Supes returns to Earth via a space warp.
As a side note, it turns out Adam had already heard about Superman because his mother had mentioned him many times before in telling him about Earth.