E.C. Tubb 
Planet of Dread 
Cap Kennedy Book 10

ENTER DR. KAIFENG . . .Of all possible enemies, Cap Kennedy had yet to cross swords with the legendary master of galactic villainy, Dr Kaifeng. In the struggle for the mind of the tyrant of Papan, they finally met — and Kennedy was the loser.There was only one chance to save the situation and that was to pay the price of the enigmatic super-surgeons of the Kraid. He would have to take a role in their eternal play-acting. The stage would be the past, a barbaric world of swords and sorcery. Kennedy would be just a sword-wielding freebooter with a crew of murderous puppets at his back. And if he survived, Kaifeng would be waiting at the stage door.