Get ready to see a different James Gordon when Fox's Gotham returns Monday.

When viewers last visited Gotham City, Gordon (Ben McKenzie) got wrapped up in a plot concocted by overeager D.A. Harvey Dent (Nicholas D'Agosto) to catch the supposed murderer of Thomas and Martha Wayne. When that suspect ended up shot dead by Gordon's gun (though not by Gordon's hand), Mayor James (Richard Kind) reassigned Gordon to a security detail at Arkham Asylum — a demotion Gordon decided to take rather than cave to City Hall's hopes that he would quit.

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Although Gordon seems to be taking everything in stride on Monday's episode (8/7c, Fox), creator and executive producer Bruno Heller says this is an important turning point in the story. "The first half of the season was very much Gordon seeing his way in this strange new world — being surprised and shocked and disillusioned, and then deciding that he's got to do something about this," Heller tells TVGuide.com. "Arkham Asylum is kind of a way station for him that gives him a chance to stop and really think about what he's doing and what he needs to do. The second half of the season is 'no more Mr. Nice Guy.' He decides and commits himself to becoming the Commissioner Gordon that we all know and love."

While Gordon's stay at Arkham is by no means permanent ("As soon as he's in Arkham, job No. 1 is, 'How the hell do I get out of here?' which he does in good time," Heller teases), could being trapped in such a dark place skew Gordon's view? Not really, according to Heller.

"Righteous anger invigorates him and energizes him and makes him happy, to a degree," Heller says. "He's the old-fashioned, white-knight crusader figure who needs a monster to fight. Needs a battle that needs winning, and he's got one. The second half of the season is him getting tough and pushing forward, but also beginning to gather around some people who feel the same way."

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Enter Dr. Leslie Thompkins (guest star Morena Baccarin), a physician at Arkham who crosses paths with Gordon when one of the inmates gets bruised up pretty badly in a brawl. "She's really smart and pragmatic — she's one of the good guys," Baccarin says of her character. "She's seen it all and can get down and dirty with the best of them. But she doesn't fall into the corrupt Gotham world. She wants to make it a better place."

That attitude make Leslie and Jim a natural pair. "He's been doing this on his own, and I think he's happy to find an ally," Baccarin says. "She comes out of nowhere for Jim and he doesn't expect to find somebody like her working in that place. It's very refreshing for him. They have this immediate connection... based on just how insane everything is around them. They find solace in each other. It's the beginning of a really great, great friendship."

Or perhaps more than just friendship? After all, Gordon's fiancée Barbara (Erin Richards) was last seen in bed with her former lover Montoya (Victoria Cartagena). "There's definitely chemistry — so I'm not going to say no!" Baccarin teases. Adds Heller: "What Gordon sees in Leslie is what he doesn't see in Barbara, which is a warrior soul — someone with a touch of iron about her, someone who is equally committed to doing the right thing, whatever the cost. Someone who is as serious as he is, but also someone who can bring the lightness out in him. That puts him in a very difficult situation because he's still deeply involved with Barbara in one way or another, and he's an honorable man. But the heart wants what it wants."

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As Gordon continues his rise toward the light, expect Penguin (Robin Lord Taylor) to continue his descent into darkness. And even though he seems to be outsmarting players on both sides of the mob war he's in the middle of, he still has a long way to go before becoming the boss. "He's playing an extremely dangerous game that most people would be too frightened to play," Heller says. "Penguin is someone who is ultimately a survivor. However, his reach always exceeds his grasp. ... The course of his crime does not run smoothly for him. I'd say he's too ambitious for his own good. There's a lot of ups and downs for him as he rolls forward, and is life is at stake many times before the season is over."

And of course, the first season won't be over as soon as originally intended, as Fox announced in the fall that the original episode order of 16 had been extended to a full 22. Heller says he welcomes the additional episodes, but insists that it doesn't change his plans for where the first season's story will ultimately end.

"The joy of this universe is that there's a million stories to tell. We never run out of stories," Heller says. " It wasn't like, 'Oh, sh--, how are we going to tell six more stories of this world? There was an ending that we wanted to get to at the end of the season, and it's still there. [The increase] has allowed us to stretch out a little and tell the stories in a fuller way, in a more emotionally engaging and exciting way.

"So it's all good," he continues. " It's a real blessing to get these extra stories because we're very aware that there are elements that people are anxious and waiting and expecting to see. If you don't deliver them because of time reasons, it's disappointing. So the more time we get, the more chance we get to deliver those little Easter eggs and gifts."

Gothamreturns Monday at 8/7c on Fox.