The novel is set in the year 2312, in the great city of Terminator on
Mercury, which is built on gigantic tracks in order to constantly stay in the planet's habitable zone near the
terminator. Swan Er Hong, an artist and former asteroid terrarium designer, is grieving over the sudden death of her step-grandmother, Alex, who was very influential among the inhabitants of Terminator. After the funeral procession, a conference is held among the family and the close friends of Alex, some of whom Swan has never heard of. This includes Fitz Wahram, a native of the moon
Titan, and Jean Genette, a police detective who has been exiled from Mars. Following the conference, Swan goes to
Io to deliver a message to another friend of Alex's, called Wang, who has designed one of the largest qubes, or
quantum computers. While Swan is visiting Wang on Io, an apparent attack of some sort fails. An attack on Terminator shortly follows; a meteorite of artificial origin destroys the city's tracks, stopping the city and exposing it to sun, essentially cooking it. As Swan travels, she learns more of the mystery surrounding her grandmother's death and the destruction of her home-city of Terminator. With Wahram and Genette, Swan travels throughout the Solar System and investigates an escalating series of conspiracies. Inspector Genette eventually discovers how the artificial meteorite that destroyed Terminator was created: someone launched a large number of smaller objects on trajectories that would eventually cause them to coalesce above Mercury, but low enough that the planet's defense system could not destroy the now large object in time. The complexity of the attack leads Genette to determine that quantum computers must have been used. Eventually the characters learn that the attack was motivated by conflicts within the
Venusian government, in the course of which a number of qubes in humanoid bodies have been secretly manufactured and sent to infiltrate human society. The humanoid qubes are arrested, along with a small number of humans involved in this conspiracy, and exiled on board a
generation ship leaving the solar system. Meanwhile, Swan and Wahram become involved in restoring and
rewilding the climate-change-ravaged Earth by returning thousands of species from space-based habitats to their home environments on the Earth. Swan and Wahram fall in love over the course of the novel, marrying at the end. ==Characters==