In the twenty-fifth century, the effects of overpopulation and global warming on Earth have led to the formation of human colonies on the Moon, Mars, and elsewhere in the solar system, yet the limited number of viable places forces humanity to look to the stars. A crash program has been developed to send Protos 1, a giant multigenerational starship, to a newly discovered Earth-like planet orbiting a nearby star. The plan is for awake crewmembers to run the ship and for people in suspended animation to be roused before planet fall to use their skills in exploration and colony formation.

To fulfill the goals of the mission and ensure that the in-flight population does not deplete the limited resources, the Protos Mandate is set up to govern a tightly controlled social system for the duration of the journey, which will take several generations. But problems threaten to sabotage the mission during its launch and transit and what finally awaits the crewmembers shocks them in an unpredictable way. This novel chronicles the trials and tribulations of this epic first interstellar mission.