With the identity of the Witness - the engineer of the reality ending Army of the 12 Monkeys - now known, Cole and his allies must travel through different eras in history to stop him.
In the apocalypse of 2163, a desperate Cole searches for Titan. Meanwhile, a captive Railly is faced with an impossible choice as the 12 Monkeys await the arrival of The Witness.
While searching for Jennifer Goines in post-WWI France, Cole and Jones encounter a dangerous group of time- travelers - the Guardians.
Bonds of trust are tested when Ramse returns to the facility with an old enemy held captive. How far will Cole and Jones go for the answers they need?
Ramse and Cole splinter to 2007 expecting either a trap - or a final chance to kill The Witness. But when Cole discovers a heartbreaking truth, he’ll discover that the mission was both.
Out of time and in need of answers, Jennifer and Deacon are sent to 1989 to steal a sacred document. Can Railly and Cole get to the Word first before it reveals the one secret they want kept?
In 1953, Cole and Railly reunite with Agent Gale at the birth of the Army of the 12 Monkeys.
Cole and Railly find themselves at opposite ends of an unspeakable decision. Jones grows suspicious while Railly turns to an emotional ally for advice. All hell breaks loose during a massive fire-fight.
Friends and enemies converge in Victorian London to await the arrival of The Witness. Cole and Railly lead their pursuers on a manhunt through time.
Cole and Railly finally learn the heart-breaking life story of the man who calls himself The Witness, the reason why he wants to destroy time and all reality is revealed.