Although we haven't seen him in the (pale) flesh in Gotham's fifth and final season, Cameron Monaghan's Jeremiah Valeska is now perhaps one of the most important characters on the series. Going into Season 5, we believed that Jeremiah would take his final steps towards becoming the one true Clown Prince of Crime, but now it seems Gotham will take another unexpected turn by introducing a mysterious third character played by Monaghan.

In an interview with Entertainment Weekly, Monaghan revealed that the character he had the most fun playing is one who hasn't been on the series yet: "The character I most enjoyed playing is the one in the final episode that we haven’t seen yet."

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So who could this character be? A third Valeska brother? A resurrected, and quite different, Jerome? Whatever the answer is, it will come in the final episode of the series, which appears to be set 10 years in the future.

"All I’ll say is when you have an episode that’s a full-on Batman episode running around in the future, you’re going to have characters that you’ll expect to see," Monaghan continued. "I don’t think it’s a spoiler to say at this point that it’s 10 years in the future — that’s been talked about openly by the producers and showrunners — I don’t want to say exactly what my role in that is, but it was kick ass. It’s one of the coolest opportunities I’ve ever had."

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Considering that a recent trailer for Season 5 teased the Dark Knight, we will likely see Batman and the Joker fighting for the soul of Gotham City in the series finale. Pictures from the set of the finale also revealed both Penguin and Riddler wearing comics-accurate costumes. Whoever this mysterious third character will be, odds are it might finally be the real Joker.

Airing Thursdays at 8 p.m. ET/PT on Fox, Gotham stars Ben McKenzie as James Gordon, Donal Logue as Harvey Bullock, David Mazouz as Bruce Wayne, Robin Lord Taylor as Penguin, Camren Bicondova as Selina Kyle, Erin Richards as Barbara Kean and Sean Pertwee as Alfred Pennyworth. The fifth and final season premiered on Jan. 3, and will run for 12 episodes.