The Prisoner of Zhamanak

Blurb

The Prisoner of Zhamanak is a science fiction novel written by L. Sprague de Camp, the eighth book of his Viagens Interplanetarias series and the sixth of its subseries of stories set on the fictional planet Krishna. Chronologically it is the fourth Krishna novel. It was first published in hardcover by Phantasia Press in 1982, and in paperback by Ace Books in April 1983 as part of the standard edition of the Krishna novels. An E-book edition was published by Gollancz's SF Gateway imprint on September 29, 2011 as part of a general release of de Camp's works in electronic form.
As with all of the "Krishna" novels, the title of The Prisoner of Zhamanak has a "Z" in it, a practice de Camp claimed to have devised to keep track of them. Short stories in the series do not follow the practice, nor do Viagens Interplanetarias works not set on Krishna.