Kid Flash, aka Wally West, is officially a full-fledged member of DC's Legends of Tomorrow. The Flash star Keiynan Lonsdale will join Legends as a series regular starting in episode 13.

“We loved working with Keiynan in our series premiere — the episode in which we learned that in between seasons 2 and 3 he had been fighting crime in Central City with Nick Zano’s Nate Heywood. So when his character stepped away from Flash to go on walkabout, after being dumped and feeling somewhat estranged from his family and team, we knew that Wally West would fit in perfectly on Legends,” executive producer Phil Klemmer told Entertainment Weekly.

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“After all, our show is about a collection of unlikely heroes who all began their journeys questioning who they are and where they belong — only to find those answers while traveling through time and having wacky adventures," he continued. "So now, Wally West is not only back in the company of old friends from the Arrowverse, he’s fighting alongside a former enemy and career arsonist Mick Rory [Dominic Purcell]. By the end of this season, Wally will learn that the Legends have a different definition of what it means to be a hero.

Rumors that Kid Flash would join Legends have circled ever since Martin Stein was killed in action and Jefferson "Jax" Jackson decided to step down from the team.

Lonsdale's Kid Flash appeared briefly in the Season 3 premiere, where he came to Citizen Steel's aid to stop a petty crime. The Legend, stranded in 2017 after Rip Hunter's Time Bureau disbanded his team, had turned to crimefighting in Central City and got a little more help than he bargained for when Wally swooped in and stole his thunder by making short work of his opponents.

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On The Flash, Wally has been largely absent. He left the team and Central City for Blue Valley in order to focus on himself. He returned for Barry and Iris’ wedding, but only stuck around long enough to keep guard of his father and sister when Nazis from Earth-X invaded, appearing only in Supergirl's chapter of the crossover. The character was shelved from the show due to the financial strain of having two speedsters, though “more exciting” stuff was teased for his future.

Returning Monday, February 12 at 8 pm ET/PT on The CW, Legends of Tomorrow stars Caity Lotz, Brandon Routh, Tala Ashe, Amy Pemberton, Dominic Purcell, Maisie Richardson-Sellers, Nick Zano and Keiynan Lonsdale.