The Chelgrians are a race of centaur-like cat aliens with three hind-limbs and a humanoid catlike torso. Major Quilan, a Chelgrian, has lost the will to live after the death of his wife, killed during the Chelgrian civil war that resulted from the Culture's interference. A high-ranked Chelgrian priest offers Quilan the chance to avenge the Chelgrians who died by taking part in a suicide mission to strike back at the Culture. His "Soulkeeper" (a device normally used to store its owner's personality upon their death) is equipped with both the mind of a long-dead Chelgrian admiral and a device given to the Chelgrians by a mysterious group of Involved aliens that can transport wormholes through which weapons can be delivered. Quilan is then sent to the Culture's Masaq' Orbital, ostensibly to persuade the renowned composer Mahrai Ziller to return to his native planet Chel, but in reality on a mission to destroy the Orbital's Hub
Mind. To protect him from detection at Masaq', Quilan's memory is selectively blanked until he reaches his target, thus preventing the Mind from reading his thoughts. Ziller lives in self-imposed exile on Masaq', having renounced his privileged position in Chel's caste system. He has been commissioned to compose music to mark a climactic event in the Idiran-Culture War. Upon hearing of Quilan's visit, and suspicious of his reason for travel, Ziller scrupulously avoids him. Quilan succeeds in placing the wormholes in the Orbital's Hub, but the Mind was already aware of the plot because Quilan's operator, the long dead admiral housed in his Soulkeeper, is actually a turncoat spy for the Culture. Although unable to track the locations on the other ends of the wormholes, the Mind suggests that the Involved "aliens" assisting Quilan's mission may have been a group of bellicose Culture minds seeking to keep the Culture from being too complacent. Having struggled with painful memories of the Idiran-Culture war, when it was the General Systems Vehicle
Lasting Damage, the Mind reveals to Quilan that it intends to destroy its own higher functions, essentially committing suicide, and offers to take Quilan with it. Quilan, who had become unsure of his own mission after experiencing dreams of his dead wife wearing the silvery skin of the Mind's avatar, agrees. They both commit suicide simultaneously during the climax of Ziller's concert, leading to much shock and outrage. At the end of the novel, a nightmarishly efficient
E-Dust Assassin is unleashed by the Culture in 'retribution' against the Chelgrian priest who acted as a pawn for the bellicose Culture Minds, as well as his immediate co-conspirators. The assassin kills the priest gruesomely by transforming into a swarm of insects that eat him from the inside out. Throughout the book there is a subplot about a Culture ethologist named Uagen Zlepe spending his time on a distant alien
air sphere and discovering hints about the Chelgrian plot to destroy the Masaq' Orbital's Hub Mind. He attempts to warn the Culture, and the reader is led to believe that his intervention is the reason why the Mind knew about Quilan's sabotage, but ultimately he fails to get his message out and is killed by one of the Chelgrian conspirators. His dead body is resurrected using alien technology an entire
galactic grand cycle later, hundreds of millions of years after the events of the story have ended. Back in the present, the Chelgrian admiral Huyler's personality, kept alive from Quilan's Soulkeeper, and the real source of the Mind's foreknowledge regarding the attack, is given a new body and becomes an ambassador to the Culture, enjoying a very high standard of living. He says he is close to convincing Ziller to return to Chel, fulfilling Quilan's cover mission. The T.S. Eliot poem which the novel takes its name from is, in part: The fate of Phlebas in the poem is similar to that of Uagen Zlepe in the novel. The title may also refer to the state of mind of the Masaq' Orbital Hub Mind and Major Quilan, both already having died in spirit during their respective wars. ==Reception==