Fans of "The Flash" have already seen Robbie Amell on the series in flashbacks as Ronnie Raymond, fiancee to Caitlin Snow (Danielle Panabaker) and structural engineer for the S.T.A.R. Labs particle accelerator, who was trapped in its core chamber before the explosion. Given Ronnie Raymond's comic book history, it should come as little surprise that Robbie Amell is set for a return to the show -- but he's going to look very different.

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While speaking with Access Hollywood, Amell said that viewers might not even recognize him at first when he reappears on "The Flash."

"I look ridiculous when you see me next," Amell told Access Hollywood. "Most people won't even recognize me for a couple seconds when you see my character return -- but you'll know it's Firestorm shortly after." The actor also noted that he will return wearing a wig and fake facial hair, and went on to discuss the involvement of Victor Garber -- who is set to play Dr. Martin Stein, the other half of the Firestorm character.

"You don't know if I'm good or bad when I show up, and you will find out that there's something going on mentally. I'm not exactly the same person I was when I left," he said. "I've got Victor Garber in my head, which is terrifying because Victor Garber is this amazing, incredible actor and I have to do a Victor Garber impression for a bit of an episode, which is an actor's dream and an actor's nightmare."

Amell further teased that both he and his cousin -- "Arrow's" Stephen Amell -- will both appear in the "Arrow" crossover episode of "The Flash."

"The Flash" airs Wednesdays on the CW.