Over the years, the Valeska Twins have become the most beloved villains on Gotham, fully embracing the twisted elements of the Joker to provide Bruce Wayne with a psychotic and worthy adversary. Both characters have been incredibly well-written, but its the performance of Cameron Monaghan that has made the Valeskas so memorable.

Since his debut as Jerome in the show's second season, Monaghan has won over the hearts of fans with his inspired performances. While Jerome, and now Jeremiah, quickly became a crucial part of the fabric of the series itself, Monaghan wasn't sure if the fans would even be into his performance.

During a visit to the set of Gotham earlier this year, ComicBook.com spoke to Monaghan about his two proto-Joker roles, and he said that he thought that he could have been finished after just one appearance as Jerome.

"No, I didn't know what to expect," Monaghan admitted. "I didn't know for sure if I was going to do more than that one interrogation scene in that first episode I was in. I didn't know if I was going to be able to touch the character again, so to be able to have this much fun and to give multiple iterations of that character and then to play another version of this, it's been insane. It's been so cool."

Of course, as we all know now, Jerome was an instant hit with fans. After his debut in Arkham Asylum, Jerome was an immediate mainstay, with viewers asking to see more of him right away.

Jerome is no longer on the series, but his Season 4 death paved the way for Jeremiah, his even more dangerous twin brother, who emulates a more calculated version of the Joker.

"I've enjoyed them both for different reasons," Monaghan said. "It was cool with Jerome how it was so heightened and kind of cartoony and insane and I could go in any direction with it because he was just this weird ball of destructive energy. It's nice with Jeremiah to find some glimpses of humanity within him and to bring him back and to make him colder and more chilling in his [methods]. I'm also doing something a little different with this season as we're continuing to develop the character than where he was at last. He was very systematic and completely irrational last season. Now he's starting to, because he's starting to lose his sanity and he's slipping away without even realizing that he is. He has too much of an ego to realize that he's slipping. I get to play around more and move around more within the character and I'm having a bunch of fun with this part, too, and also where it's going is extremely exciting and I can't wait to hit a couple of these story weeks that are coming up."

Which Valeska brother is your favorite? Are you looking forward to what Jeremiah will bring to Season 5? Let us know in the comments!

Gotham's fifth and final season is set to arrive on Thursday, January 3, 2019 on FOX.