MacLaren, his team and their loved ones regroup at a safe house protected by the FBI, but doubts and betrayals may sabotage the rest of their mission.

The team attempts to extract a rogue A.I. from a child messenger, but the program expands too rapidly. A new Traveler adjusts to his host.

Suffering from a fatal brain disorder, Trevor makes the choice to allow himself to be overwritten as the team races to invent an experimental cure.