Starred Review. This magnificent eighth novel (after 2000's Look to Windward) of the Culture, an interstellar posthuman civilization of incredible wealth and technological sophistication, centers on three siblings: Ferbin and Oramen, the misfit heirs of conquering King Hausk of the Sarl, who rules a backward and patriarchal realm deep beneath the surface of the artificial Shellworld Sursamen, and their exiled sister, Djan, now a powerful agent of the Culture's Special Circumstances division. When King Hausk is murdered, Ferbin narrowly avoids the conspirators and sets out across the galaxy to ask Djan's help with revenge against the killer, now serving as Oramen's regent. Soon they learn of the horrific forces a hidden enemy is about to unleash on Sursamen, and must race to save the home that has rejected them both. Beautifully written and filled with memorable characters and startling technology, this tale of intricate politics and interstellar warfare ably demonstrates that Banks is still at the height of his powers.