As political tensions rise in 2176 America, time travel is stirring up the race-related sins of the past. Investigating alterations to history during the Revolutionary War, George Merrill and Andy Bishop find their newly-restored friendship severely tested, and the challenges continue at home: mysterious disappearances, painful family conflict, unwelcome publicity, and strange happenings at the Time Travel Institute. Seeds sown decades before are breaking dormancy: the awakening of an intelligence that relies on humans to flourish and spread, and that threatens the stability of time itself.