Shattered by recent losses and a sweeping new protocol, the Travelers face a bleak future with only one long-shot chance to succeed in their mission.
The Faction sets off nuclear blasts that destroy all of the Travelers' archives, except the one in which a wounded David just happens to be trapped.
MacLaren urges Yates to help him when a Traveler with a mission vital to humanity's survival arrives in the body of a just-captured serial killer.
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.
The Faction kidnaps Philip and a group of other historians, forcing MacLaren and the team to extract their location from a critically injured Hall.
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.
The team learns that Traveler 001 is still alive when the Faction tries to capture him. Doubts about their loved ones worsen for Kat, Jess and David.
Certain that his team erased his memory of the previous day, MacLaren retraces his steps in the case of a disturbed youth with a horrific future.
MacLaren and Yates adjust to their new partnership while protecting a TV show host whose inflammatory rhetoric about Travelers has led to tragedy.
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.