Five hundred years ago, humanity received an invitation from an alien artifact to colonize a distant solar system. Today, three fleets of generational ships come into conflict as they converge on their destination. The Theists and Collectivists want only their independence, but the leader of the Imperials is determined to bring them into his Empire.

As cultures collide and politicians play games, it becomes obvious that the artifact's benevolent offer is not what it seems. Instead of the promised utopia, the humans discover an ancient cold war.

Among the fleets is a stranger, a man named Gabriel lacking neural augmentation and any recollection of how he came to be there. He might hold the key to the survival of the fleets, but Gabriel feels no gratitude towards people who despise him as an unwelcome burden.

They needed a hero. They got something else.