John Carter, mighty Warlord of Mars, rides to new and terrifying adventures. Captured by deadly warriors mounted on huge birds he is taken to the ill-omened city of Morbus. There he meets Ras Thavas, evil genius and master surgeon. A man who has succeeded in his nightmare wish of creating life in his own beings - creatures that ultimately rebel and threaten the lives of Ras Thavas, of John Carter and all of Mars