With just under one month until The Flash returns with the midseason premiere Potential Energy, a new report reveals that Barry Allen (Grant Gustin) will have to contend with a familiar foe in the back half of Season 2. Entertainment Weekly reports that Matt Letscher has signed on to return as Eobard Thawne, a.k.a. Reverse Flash. The actor is set to return in Season 2's 11th episode, fittingly entitled Reverse Flash Returns.

In Season 1, it was revealed early on that Harrison Wells (Tom Cavanagh) was the Reverse Flash, but towards the end of the season, we learned that was only part of the story. As it turns out, the real Harrison Wells is dead, but Eobard Thawne (Matt Letscher), who traveled back in time to kill Barry Allen's mother, absorbed Wells' DNA and took on his persona to train Barry with his new speedy powers. In the Season 1 finale, Eobard's ancestor, Eddie Thawne (Rick Cosnett) sacrificed himself, which essentially erased Eobard from the timeline. Here's what executive producer Todd Helbing had to say about Eobard Thawne's return.

"His impossible return to Central City puts a member of the S.T.A.R. Labs team in unexpected danger, forcing Barry to make a life-changing decision."

While it isn't known how Eobard will return to Central City, it certainly seems possible that this could be the Earth-2 version of Eobard. It isn't known if Matt Letscher is set to come back for any other episodes besides Reverse Flash Returns, which is slated to air Tuesday, January 26, one week after the midseason premiere Potential Energy airs on Tuesday, January 19. When he does come back, though, he won't be the first character to come "back from the dead," so to speak.

Despite Harrison Wells already being dead, the show's exploration of Earth-2 allowed for Tom Cavanagh to return as a different version of Harrison Wells. We've seen in the first half of Season 2 that Barry is finally starting to trust the Earth-2 version of Wells, a relationship which could be in danger with the re-emergence of Reverse Flash. Other characters who are already confirmed for the back half of Season 2 include Marco Grazzini as the villain Tar Pit and Adam Stafford as Geomancer.

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Fans will also learn a lot more about Keiynan Lonsdale's Wally West, who was introduced in the fall finale Running to Stand Still earlier this month. In the comics, Wally becomes "Kid Flash," but it still isn't known if he will turn into Kid Flash by the end of Season 2 or not. Matt Letscher has previously had recurring roles on Scandal, The Carrie Diaries and Boardwalk Empire. What do you think about Reverse Flash returning in Season 2 of The Flash?