Urthona was a powerful sorcerer from the planet Gevaltu. He intended to replace Stephen Strange as Sorcerer Supreme of their dimension, and managed to steal away the Sanctum Sanctorum to his homeworld. Having injured Strange and claimed his totems and tomes, Urthona declared himself the new Sorcerer Supreme. Doctor Strange and Rintrah followed Urthona to Gevaltu, however to retrieve the Sanctum and Strange's hostage friends. Stephen made the decision to destroy his Sanctum's objects of power rather than let them fall into Urthona's hands.