Things are certainly getting interesting on Gotham.

On Monday's episode (8/7c, Fox) — the last before taking a few weeks off — Gordon (Ben McKenzie) is shocked to learn from Harvey Dent (returning guest starNicholas D'Agosto) that all of Gordon's charges against dirty cop Arnold Flass (Dash Mihok) are being dropped. The reason? Commissioner Loeb (guest star Peter Scolari) has a "mystery witness": Gordon's partner Harvey Bullock (Donal Logue)! Apparently, Loeb has used the dirt he has on Bullock to make him recant his testimony against Flass.

Gotham boss Bruno Heller teases "the beginning of the Joker saga"

"What Jim doesn't know about me is I have some skeletons in my past that Loeb is aware of," Logue says in the exclusive behind-the-scenes video below. "That's something Loeb likes to do with a lot of people. If certain things are brought to light that could be the end of my career. I don't want to reveal the sins of my past, and it makes it difficult for me to want to participate in doing the right thing."

As a result, Gordon decides he needs to destroy Loeb's treasure trove of blackmail. But he may need a little help from Oswald Cobblepot (Robin Lord Taylor) to pull it off. "[Jim] knows that Oswald's effective and can get things done," McKenzie says. "He has no better option, so he uses it."

But what price will Jim pay for that decision? Click play below for more intel and exclusive scenes from Monday's episode now!