The Hostage of Zir

Package tourism has reached the planet Krishna, and Fergus Reith is to guide the first party from Earth through its sorcerer-kingdoms. First he must learn Durou, swear a chemically enforced oath to pass on no technology, and learn the broadsword. The broadsword matters most. Third in de Camp's Krishna series, first published in 1977; Paul Alexander painted this Ace cover.