Lynn goes head to head with Dr. Jace once and for all; Gambi risks his life to save Jennifer; Tobias makes a major move to cripple Freeland and kill Black Lightning.

When presumed-dead billionaire playboy Oliver Queen returns home to Starling City after five years stranded on a remote island in the Pacific, he hides the ways the experience has changed him. As he reconnects with those closest to him, including his sister, Thea, Oliver appears to be the same wealthy, carefree bachelor they've always known. At night, flanked by his devoted friend, Diggle, Oliver uses his secret persona -- that of a vigilante -- to right societal wrongs and transform the city to its former glory.

At 11, Barry Allen's life changed completely when his mother died in a freak accident and his innocent father was convicted of her murder. Now a crime-scene investigator, his dedication to learn the truth about his mother's death drives him to follow up on every new scientific advancement and urban legend. When his latest obsession -- a particle accelerator heralded as a world-changing invention -- causes an explosion, it creates a freak storm and Barry is struck by lightning. He awakes from a coma nine months later with the power of superspeed. When he learns that others who have gained powers use them for evil, he dedicates himself to protecting the innocent, while still trying to solve the older mystery.

"Arrow" and "The Flash" have some new superhero company in the CW's lineup with the addition of "DC's Legends of Tomorrow." After seeing what doom the future holds, time-traveling rogue Rip Hunter realizes heroes alone are not enough to prevent the impending catastrophe that threatens not only the planet, but all of time itself. Tasked with recruiting both heroes and villains, Rip brings together a ragtag team of divergent talents, which includes the likes of Sara Lance, Ray Palmer, and Heat Wave.

At 12 years old, Kara Zor-El escapes doom on planet Krypton to find protection on Earth with the Danver family, where she grows up in the shadow of her foster sister, Alex, and learns to hide the extraordinary powers she shares with her cousin, Superman. Now an adult living in National City and working for media mogul Cat Grant, Kara finds her days of keeping her abilities a secret are over when super-secret agency head Hank Henshaw enlists her to help protect the city's citizens from threats. Finally coming into her own, Kara must juggle her new responsibilities with her very human relationships.

James Gordon is a rising detective in the dangerously corrupt Gotham City, where his late father was a successful district attorney. Brave, honest and determined to prove himself, Gordon must navigate the dirty politics of Gotham's justice system as well as the rise of malevolent villains like The Penguin, The Riddler and Catwoman. The series also chronicles the life of young Bruce Wayne, who becomes an orphan when his billionaire parents Thomas and Martha Wayne are murdered. Gordon becomes a friend to young Bruce as he finds his way toward becoming the iconic caped crusader.

When a group with nefarious intentions attempts to change the world as we know it by altering the past, Lucy, a historian, Wyatt, a soldier, and Rufus, a scientist, unite to form an unlikely partnership, traveling through time to save history. Their riveting adventures take them to some of the most thrilling, volatile and critical events on record, including a venture to the Old West, a sojourn to the Alamo, a visit to the famous Chicago World's Fair and a crusade into Nazi Germany. Along the way, they cross paths with famous historical icons, such as Josephine Baker, Harry Houdini, Ernest Hemingway and infamous rivals Eliot Ness and Al Capone. But every step the team takes to protect history puts everything we know at risk -- because changing one thing changes everything.