Wally West Joins 'Legends of Tomorrow' in "Here I Go Again"

After quite a bit of anticipation from fans, a familiar Arrowverse face prepared to step on board the Waverider in tonight's Legends of Tomorrow.

Spoilers for tonight's Legends of Tomorrow, "Here I Go Again", below!

Tonight's episode largely focused on Zari Tomaz (Tala Ashe), the only member of the team to not be stuck in a somewhat unusual "time loop." By the episode's end, Zari, with the help of Gideon (Amy Pemberton), had returned back to the normal timeline, only for audience members to be met with a unique surprise in the closing scene.

Rip Hunter (Arthur Darvill) traveled to 2018 to track down The Flash's Wally West/Kid Flash (Keiynan Lonsdale), telling Wally that the Legends need his help in saving the universe.

The idea of Wally making the jump from Flash to Legends has been kicking around in fans' minds for quite a while now, especially after Wally briefly appeared in Legends' season three premiere. Following the departure of both halves of Firestorm - Martin Stein (Victor Garber) and Jax Jackson (Franz Drameh) -- those involved with the show hinted that an existing Arrowverse character would be joining the show, with Wally being floated as one of the main theories.

Exactly a month ago, Lonsdale was added to the show, and fans have been excited to see him join the team ever since. And while Wally hasn't officially united with his new teammates yet, according to some of his Legends co-stars, Lonsdale bringing his Wally role onto the show will manifest in some interesting ways.

"Yeah, you know, I think that goes with the talent that Keiynan brings to his role and to this newly-forming — is it forming? — energy of him coming in to be a part of our show for a little bit," Brandon Routh, who plays Ray Palmer/The Atom, told ComicBook.com last month. "I think for the most part, our writers are writing for us as a team and putting the team first. And if we can make poignant stories about cultural differences or religious differences, then we do. But if we can't, then we are all working together on the team to solve history, which is I feel like a place that we can get to in the world, where we can understand that we all have differences but we can all talk person to person, human to human."

While he can't be seen in the promo, fans will hopefully start to get an idea of how Wally interacts with his fellow Legends in next week's pirate-themed episode, "The Curse of the Earth Totem".

Legends of Tomorrow airs Mondays at 8/7c on The CW.