Amid the teeming populace of Gotham City are numerous big, bold personalities. Many are vying for power, while others are simply trying to retain their sanity. And while a good portion of "Gotham's" biggest and baddest threats wear their intentions on their sleeves, it's the quiet ones you truly have to watch out for.

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Take, for example, Edward Nygma, the Gotham City Police Department's resident forensic scientist. Meek, kind and meticulous with a flair for cryptic riddles, Nygma appears relatively harmless -- of course, Officer Tom Dougherty ( Zachary Spicer) discovered that this is far from the case. When he stabbed Dougherty to death in "Gotham" season 1, it was the first truly obvious sign the tightly wound Nygma was beginning to crack. And, as actorCory Michael Smith tells CBR News, there's plenty more of that to come as his character continues to change over the course of "Gotham's" Season 2, which premieres tonight on Fox.

CBR News: In Season 1, Nygma killed Kristen Kringle's abusive boyfriend, Tom Dougherty. Was that merely out of self-defense, or were those his intentions all along?

Cory Michael Smith: Totally self-defense.

I love how they wrote that; the thing I've been so happy about what the writers and producers have done with Edward, is that they make sure his intentions are pure at the beginning and not someone who is starting out as wanting to be a badass. He's someone who wants to be a good person, but is failing miserably. No one understands him or appreciates him.

When we were working on that scene, it was a genuine surprise for Edward, but also invigorating. It's the first time he's really stuck up for himself, and in this massive sort of a way. Getting rid of this terrible person and doing something that almost feels like justice, all of those things happening and colliding at the same time, his brain explodes. That was a very bold moment.

As the season closes, Nygma seems to be cracking. What's his state of mind at the beginning of this season?

When we pick up, we're picking up right at the end of Season 1 for the most part. Afterwards, we move along a couple of weeks. Jim Gordon (Benjamin McKenzie) is kind of displaced, and then we realize when we meet Ed that Ed has been spending a couple of weeks in a similar state that he was in for those final episodes, except way more distressed. He's been talking to himself. He's cracked open. He's literally cracked, and from his bruised head, what has emerged is what I like to think of as his ego and his id. These two fractions of him are battling. One is the Edward we know, and the other is the Edward who wants to be the Riddler. He certainly is not the Riddler you know.

Nygma talks to himself. He hears voices. Do you feel there is a Dr. Jekyll and Mr. Hyde dynamic there?

Absolutely, there is. What the writers have done, which is so exciting, is make these two parts of him so real, but it's clearly just all in his head. As much as we'd love embracing the comic book element of the show, what's so terrifying is how clear both of these identities are. It's just this conversation with him. This person comes and goes very quickly.

What's this voice encouraging Nygma to do?

It's an aggressive older brother encouraging Ed, or coaching Ed, on how to get the very things that he wants, which is power, love and sex. It's all the things that any normal male wants, but Ed doesn't know how to get them. This other person is both encouraging him and taunting him and reprimanding him.

Does he just embrace this new personality or is there some kind of inner or moral struggle?

There's certainly a struggle. Again, what I like about this character is, he's not a bad person. Some of the encouragements feel wrong, or abrasive, or ethically questionable. He wants to be left alone. He's also reconciling what he just did. It was both a good thing for Kristen and potentially for himself, but [it was] a horrible, despicable act. The other side of him is embracing the reality of the situation, which is, "You can't change it, but look at all the good it's going to do for you and Kristen. Take advantage of the situation." It's a beautiful place for Ed to live. I've had so much fun doing it.

Nygma's infatuation with Kristen was a catalyst of sorts for his downward spiral. Where does she factor into his life now?

His obsession and love for Kristen, if anything, has intensified. She figured out his clue, which is terrifying and exciting and arousing, sexually and intellectually. His pursuit for her and love for her is not going to diminish at all. He's even willing to take a bullet for her. He would do anything. We're going to see the expression of his devotion turned up a little bit, but not just with these cute gifts and presents. There are very real demonstrations of his adoration, with high hopes it will capture her attention and interest.

There's a changing of the guard in terms of the captain at the G.C.P.D. How does that affect Nygma?

Not too much, other than the fact that he had an ally in that position. Now, he doesn't necessarily have a friend there. If he continues behaving the way he does and gets in trouble, there's nobody to really save him. His security at the G.C.P.D. may be potentially in question if he keeps acting up.

Other than that, he's living in such a different department than the detectives. The kind of militarization that we're going to be seeing in the police force doesn't really swing over into forensics too much.

How do these villains coming to Gotham City shake up the narrative?

Last year, there was always someone causing trouble. What we've done this year is, instead of this procedural format where we have someone come in, create a conflict and all of these characters are responding to it, the conflict is coming from these villains. We'll get to understand why they are doing it, and how this small act is connected to another act, which is connected to someone else. We're building this delicious web of conflict, which is the greatest difference between last season and this season. We're in a tighter world. All of these characters are truly vicious. They make the Penguin look like a chump, sometimes. I'm super stoked, and we have some amazing actors coming in.

Nygma already had a run-in with Cobblepot. In what ways does that relationship start to evolve?

We know that Edward knows who Cobblepot is. We know he has enough curiosity and intrigue to go up and talk to him. There will be another run-in, for sure. This curiosity and admiration will begin to unpeel itself and explain itself. What Penguin does with that is another question. As we know, when Ed becomes obsessed with someone, it's full throttle.

What else can you tease about Nygma in the first block of new episodes?

We'll certainly be exploring a very rich, emotional life of Edward that we haven't seen at all, which has been really thrilling for me as an actor. I'm excited for that. The writers have given me so much to dig into. We're going to see this person grow and change. In the very first chunk of this season, as things are changing and he's listening to this other version of himself, he might even be making some friends at the G.C.P.D. This person, who was absolutely irritating and annoying, is getting trained socially, and adapting. Perhaps he's losing a little bit of his intense awkwardness. He's growing up a little bit and learning to communicate, learning how to talk to people and lie to people, and use them as he needs. He's being socially trained.

As the Riddler, Nygma becomes one of Batman's main adversaries. What makes him so deadly?

That's a great question. I think what we're working towards, at least for me, is his scaling narcissism. What is it that can unlock a narcissist? What is it that encourages a narcissist? What is it that tempers down someone's narcissism? Certainly, love is an antibiotic to narcissism. What can make someone so deadly is when they are in love with themselves, with their abilities, gifts and intelligence. That's the thing that rules them until all these other things like pride are in play. That's the thing that keeps them going. I think that's a part of Edward that makes him extremely dangerous in the future.

And while it's there, and his narcissism is totally elementary, he's not even a big player at the G.C.P.D. and has no power or respect. Once he starts getting this, and once he starts to have a standing and is able to manipulate people and he can get away with some crazy shit, his narcissism is going to be taking some steroids and growing. It's an interesting thing for a character to get addicted to. It's going to be a fun ride.

"Gotham" debuts tonight at 8p.m. on Fox