After the defeat of the immortal villain Vandal Savage and the corrupt Time Masters who colluded with him, a new threat emerges. Dr. Nate Heywood (new series regular NICK ZANO), an unconventional and charming historian, is thrust into the action upon making a shocking discovery - the Legends of Tomorrow are scattered throughout time.
Nate must find a way to rescue the Waverider's beloved team of heroes and rogues, including Star City inventor Ray Palmer (series star BRANDON ROUTH), who has created an exo-suit with the power to shrink him to miniscule size, as the Atom; Sara Lance (series star CAITY LOTZ), a trained assassin known as the White Canary; Professor Martin Stein (series strar VICTOR GARBER) and Jefferson "Jax" Jackson (series star FRANZ DRAMEH), who together form the metahuman Firestorm; and career criminal Mick Rory (series star DOMINIC PURCELL), aka Heat Wave. When the Legends encounter the Justice Society of America (precursor to DC's Justice League) in the 1940s, Amaya Jiwe (new series regular MAISIE RICHARDSON-SELLERS), aka Vixen, joins the team. While the team reunites, a mystery looms - the fate of former captain Rip Hunter (series star ARTHUR DARVILL).
Once reunited, the Legends continue their new mission to protect the timeline from temporal aberrations - unusual changes to history that spawn potentially catastrophic consequences. When Heywood, the grandson of J.S.A. member Commander Steel, unexpectedly finds himself with powers, he must overcome his own insecurities and find the hero within himself. Ultimately, the Legends will clash with foes both past and present, to save the world from a mysterious new threat.