Oliver Queen is led to the Waverider beneath the ocean's surface, where he learns that the Legends have made a fateful trip to 1942 in order to prevent the Nazis from destroying New York City with an atomic weapon -- with help from Albert Einstein.
The Legends are confronted by the Justice Society of America in the year 1942, and soon discover a time aberration that threatens the team of heroes on a mission to Nazi-occupied Paris -- unless the Legends intervene. Nate tries to connect with his grandfather, Commander Steel, and Dr. Stein is pleased to be appointed his team's new captain.
Nate finds himself in feudal Japan, taken in by a peasant woman but unable to control his newfound powers. When the team arrives in search of him, they find that a local shogun has co-opted the Atom suit for his own purposes.
The Legends chase a signal to a time pirate's ship that has crashed in Mississippi in 1863, at the height of the Civil War -- and soon find themselves with a mission to help save the Union not only from the Confederates but from soldiers who have been turned into zombies. While Jax and Amaya try to infiltrate a slave plantation, Ray and Martin deal with their own problem on board the ship.
In the 1980s the Legends pay a visit to the Reagan White House, only to encounter Damien Darhk putting into place a larger plan. Amaya and Nate go in search of the Justice Society in this time period and encounter an old friend, and Martin must prevent his younger self from putting their marriage at risk.
A return to the Old West reunites the Legends with Jonah Hex, who is trying to stop the cunning Quentin Turnbull from taking over the West -- with help from a newly-discovered mineral. While Nate puts his life on the line, back on the ship Martin experiences visions of a woman he has never met.
With help from Team Flash, Team Arrow, and Supergirl the Legends work on a plan to stop the Dominators' invasion of Earth, sending a team back to their original landing in 1951. Stein works with the daughter he never had, aware that he may have to correct his mistake and erase her from existence.
After Darhk, Thawne, and their new ally Malcolm Merlin decide to support Al Capone in 1927 Chicago, Nate and Ray take the place of Elliot Ness to try and take down the mobster. While the villains target the amulet hidden on the Waverider, Dr. Stein struggles with whether or not to reveal his secret to Sara.
The race is on to 1967 where the Legends must beat Darhk and Merlyn -- a.k.a. the "Legion of Doom" -- to Rip Hunter, who is now a film student after erasing his memories. While the enemy seeks a piece of the powerful Spear of Destiny Rip was believed to possess, Rory asks Martin for help getting rid of his visions of Snart.
Malcom Merlyn and Damien Darhk try to convince Rip to help them recover the lost pieces of the Spear of Destiny, but begin to wonder why their speedster ally is always absent. Meanwhile an eager Martin brings his daughter on board the Waverider, only to have her discover the true nature of her origins.
After the Legion rewrites Rip Hunter's identity and sends him to kill George Washington in 1776, luring the team into what they know is a trap -- leaving Sarah mortally wounded, Rory in enemy hands, and Jax defending the Waverider from its former captain.
After Rip beats the team to a piece of the Spear in the distant future the Legends travel to sixth-century Camelot, where a member of the JSA has shaped real-world history to fit the legend of King Arthur -- and where Rip and Darhk are using mind-control technology to find the next spear fragment.
Sabotage leaves the ship stranded 69 million years in the past, where Ray leads a team to locate a missing part of the Waverider. Sara and Jax go inside of Rip's head to try and rescue their friend from the villain he has become, where they encounter twisted versions of the crew.
The Legends track Commander Steel to NASA in 1970, where Eobard Thawne has infiltrated the Apollo 13 mission in order to acquire the final fragment of the Spear of Destiny. But when the Waverider experiences a disaster, Ray's life is on the line.
After stealing the final piece of the Spear of Destiny out from under Eobard Thawne's nose the Legends head to wartime France in 1916, hoping that J.R.R. Tolkien can help them find what they need to destroy the mystical artifact -- before the heroes themselves are tempted to use it to their own advantage.
The team faces perhaps its greatest challenge after the Legion rewrites reality, leaving them scattered and the villains in power -- and Amaya and Sara working for Damien Darhk. While Nate and Ray try to restore their friends' memories, Thawne plans to destroy the Spear so that his new reality will be permanent.
After suffering defeat at the hands of the Legion of Doom the reunited Legends must break a cardinal rule of time travel, returning to 1916 to try and stop their former selves from losing the Spear of Destiny in the first place.
