Triumvir Ilia Volyova of Nostalgia for Infinity is an implant-free Ultra, and a major character in both Revelation Space and Redemption Ark. At the beginning of Revelation Space, Volyova is the keeper of the Cache Weapons. It is during her search for a means to control these weapons that she enlists Ana Khouri (who was planted in the role by the Mademoiselle), thus setting off a chain of events that continues throughout the novels. She maintains a long friendship with Captain Brannigan, and is the only one to visit him regularly during several years of travel time on the Nostalgia for Infinity in which he is kept in very deep reefersleep to slow down the onset of Melding Plague in his body. She later disengages the reefersleep and warms him up fully, allowing his body to merge with the Nostalgia for Infinity as the only way to save it from an attack. Volyova later, in a plot hatched with Khouri, helps organize the evacuation of Resurgam, the first human-colonised planet doomed to be destroyed by the Inhibitors. She ultimately sacrifices herself to prevent the suicide of Captain Brannigan, now indistinguishable from the ship. In doing so, she exposes herself to vacuum, the damage proving almost fatal to her, but preserving the ship and thus the last chance of survival for the inhabitants of Resurgam.
She later dies on a suicide mission attacking the Inhibitors around Resurgam in an attempt to slow them down, giving the Nostalgia for Infinity the best possible chance of escape. Her actions apparently had no effect on the Inhibitors and all cache weapons that she took were wasted.
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