The Sunstone, which is held within the Temple of the Sun, is running out of power and must be recharged, in The Ceremony of the Sun, which takes place once a century. The Sunstone's keepers invite He-Man and his companions to the ceremony, but on the way they face trouble from Negator, who wants the Sunstone's power for himself, and even more inconveniently a Trollan called Prankster who is deliberately making a nuisance of himself and will only go home if they can guess his name.