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?