The second book in the "Expanse" series introduces the characters Chrisjen Avasarala, Gunnery Sgt. Bobbie Draper, and botanist Praxidike Meng who join the crew of The Rocinante to investigate the latest protomolecule developments. Holden and his crew are now in the employ of Fred Johnson and the OPA which has become the defacto government of the belt after the events in Leviathan Wakes. Quik-Mao corporation still cannot resist experimenting with the protomolecule despite all evidence indicating that it cannot be controlled. Their latest efforts trigger a war between Earth and Mars which threatens humanity throughout the solar system. Great follow-up to the first book and follows series two of the TV show quite closely.