Held in custody by the FBI, Grant MacLaren and his team realize that they may not be able to escape the truth about their true identities and their mission from the future. Elsewhere, the original Traveler test subject reveals his secrets to a therapist.
MacLaren must help his new partner get accustomed to the twenty-first century while they investigate a group who went missing from a hotel conference room. As the rest of the team tries to return to life as usual, Marcy helps David cope with his trauma -- and Philip makes a new friend.
After a demolition team discovers the remains of an all-too-familiar crime scene MacLaren looks for a lead on the mysterious person who once kidnapped his team -- putting them on the trail of a missing Traveler. Carly and Jeff prepare for their final child custody assessment, and David turns to Marci when an old girlfriend needs help.
Trevor and Philip help an activist complete a dangerous mission against an agricultural menace that could threaten the planet. While Kat and Grant deal with difficult news about her pregnancy, MacLaren and Carly must work with a fellow traveler to plan his own assassination.
The team deals with a viral outbreak with an historically high casualty rate, and is tasked with saving three victims -- until a mutation presents a potentially catastrophic new threat.
As the world suffers from a viral pandemic MacLaren's team pursues a stash of uranium, designed as a back-up power source for the Director. Meanwhile Grace takes it upon herself to try and cure the virus using nanite technology.
Philip receives a secret update to account for changes to the timeline, as Trevor makes an unsettling discovery about his host's past. While Kat undergoes an emergency procedure, David receives an unexpected windfall.
The team is called upon to provide added protection to a child who is important to the future, who Hall and Luca have taken into custody. Marcy undergoes a procedure to discover her past memories.
Marcy locates one of the first Travelers, a brilliant man whose host developed mental health issues after his arrival. As Marcy rekindles her relationship with David, Carly and Jeff clash.
Ingram uses the team's loved ones against them, kidnapping Kat, David, Jeff, and others and attempting to blackmail MacLaren's team into revealing their part in the Traveler program.
