When Olivia brings down the fury of Titan on Temporal Facility in 2046, the team must repel the enemy long enough for Jones to hatch a plan to splinter the entire base into hiding.
In hopes of retrieving a power core from their new surroundings the travelers must avoid creating a paradox by coming into contact with their past selves. In 2018 a pair of detectives search for Jennifer, who is attempting to discern the meaning of the ouroboros artifact.
Cassie is forced to reconsider her plan to kill Olivia as a teenager in 1971 when she meets the girl face-to-face. While the future Olivia searches for her true role, Cole encounters a puzzle in 2018.
Cole and Cassie travel to 1966 in an attempt to recover the Primaries' weapon, putting them in the path of Zalmon Shaw -- and a new and deadly cycle that Cassie might not be able to break, no matter how many times she tries.
To find the Primaries' weapon -- an artifact known as "Die Glocke" -- Katarina leads a mission to infiltrate a Nazi event in France during World War II. But things are complicated by the French Resistance, who have their own plan for the Germans.
Jones finds herself a prisoner inside the confines of Titan, where the Witness attempts to use her own memories against her. Hannah tries to integrate herself into 2007 life, while the others prepare for a dangerous splinter to 1491.
Olivia makes an ally in medieval Europe, who she hopes will help her locate the weapon first. James and Cassie turn to the Primaries to climb the steps, and Hannah and Emma have a face-to-face reckoning.
When all hope in the fight against Titan seems lost, the team discovers one last chance buried in a puzzle left for them by Jennifer. As James and Cassie return to where their story began, in 2009 Hannah convinces Emma about the role she still has to play.
As the final battle with the Army of the 12 Monkeys draws near, Cassie balks at the idea that the only way to win is to erase James Cole from history -- as James begins to close his circle. But the only way to complete the mission is for Team Splinter to enact their most daring plan yet.
With Titan on the verge of collapsing all of time, the team receives some desperately needed reinforcements from history as they take the fight to the Witness's own home turf -- knowing that one of their own must still, in the end, make the ultimate sacrifice.
