Ten thousand years after the galactic federation called Concord rescued humanity, we are poised to leave probation, accept a second homeworld, and undergo genetic engineering to make us nearly immortal. But what should have been a joyous occasion will not go smoothly.

Emma Fuji, now over ninety-five centuries old, is leading her convoy of ships on their nineteenth mission. When they arrive they find something unprecedented: a galaxy twisted by an ancient cataclysm with no signs at all of intelligent life. As the experts try to determine what happened and what to do next, an ancient army is slowly gathering to eradicate what they see as a dangerous invasion.

Meanwhile Anne, Emma's granddaughter, is traveling from a Venus on fire to a revitalized Earth, the thriving colonies on Mars, and finally to humanity's new planet Rhea, struggling with politics all the way. A rapidly growing isolationist movement is campaigning for humans to leave Concord, which would mean the end of humanity. The zealots will do anything to convince Anne and Emma to join their cause, or failing that to take them out of the equation.

And in one solitary ship, an uploaded alien mind battles against a tenacious and cunning AI that threatens the future of Concord itself.

In this stunning conclusion to the Concord trilogy, both humanity and Concord stand on the brink of extinction or evolution.