By Frank Herbert
Jorj X McKie, from Herbert's novel The Whipping Star, is back to solve a new mystery: Dosadi. Dosadi is a toxic planet where a group of humans and Gowachin were confined within a rift valley. They are trapped in the valley and along the rim by what they call the God Wall. The God Wall is maintained and powered by a Caleban, celestial beings who appear to be actual stars. No one may exit through the God Wall except via one method, which McKie discovers after he arrives in the valley.
McKie has a close relationship with one particular Caleban, Fannie Mae. In the past, he rescued Fannie Mae from torture and certain death. Fannie Mae reveals that the only way to leave Dosadi is in a different body: "McKie cannot leave in his own body/node." Eventually McKie figures out that Dosadi is being used as a source of youthful bodies into which older beings have their minds transferred. Using the power of the Calebans, one person's mind can be transferred into the body of another person, no matter their species. This is being used by the rich and powerful as a way to have eternal life. The person whose body is used is transferred into the old person's body and then killed to keep the whole process secret.
The population of Dosadi has to cope with a very hostile and dangerous environment. It has made them the ultimate survivors. They have become a threat to the rest of the civilized universe and they are determined to break free of their prison. The wealthy cabal is now fearful of the result if these people manage to gain their freedom. Their solution is the destruction of the entire planet of Dosadi and its captive population of humans and Gowachin. McKie only figure this out once he is on Dosadi. When he reveals it to the warring factions in the rift valley, it brings the conflict to an end as they come together to face this terrible threat.
This was, frankly, a rather boring read. The characters spend most of their time together trying to read each other's body language. The Dosadi are so adept at reading body language that non-Dosadi are an open book to them. Which makes it easy for them to spot non-Dosadi. So a lot of the story is about various Dosadi reading each other and reading McKie and other non-Dosadi. Kind of boring.
McKie's love interest in the story is a Dosadi woman, Jedrik, leader of one of the warring factions. She reminded me of the bitch mothers of Dune, those austere and cruel women trying to build a better society.