The Castle of Grayskull on the peaceful planet of Eternia is under threat from the power-crazed supervillain Skeletor (scene-stealing Frank Langella). Eternia's only hope of survival is a ragtag band of freedom fighters led by the heroic He-Man (Dolph Lundgren). When the brilliant troll Gwildor (Billy Barty) accidentally transports the epic fight to Earth via his Cosmic Key – a musical device that can open a portal to any location in the universe – the interstellar forces of good and evil are soon battling for ultimate supremacy in 1980s America!