Already outnumbered, the influx of villains in Season Two may mean "Gotham's" heroes are about to also find themselves outmatched as well.

In Season One, Oswald Cobblepot's elaborate scheming -- and a little bit of luck -- allowed him to take over the city's criminal underground. The Fox series also planted the seeds for Selina Kyle, Edward Nygma and Ivy Pepper to grow into Catwoman, The Riddler and Poison Ivy. However, "Gotham" Executive Producers Bruno Heller and Danny Cannon have been teasing that Season Two, subtitled "The Rise of the Villains," is where the city's proliferation of bad guys really begins. Throughout the season, a new slew of iconic Batman foes will be introduced, leaving the good guys in a situation where they'd better get their act together -- or be eliminated.

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Heller and Cannon spoke with the press during roundtable interviews at Comic-Con International in San Diego about which Batman villains viewers can hope to see in Season Two. We also discussed the Joker's presence in the first arc, Gordon's strained relationship with Barbara and the addition of good guy Lucius Fox as one of the few counterbalances to the show's constant introduction of future supervillains.

For Season Two, do you have an ongoing theme that you want to cover, or is it on an episode-by-episode basis?

Bruno Heller: There is a genuine subtitle on the show, which is, "The Rise of the Villains." It's very much about the transition from old-school, mafia-type villainy to the kind of grandiose, grotesque, gothic evil that Gotham [City] is slowly moving towards. So, the crimes are grander. The villains are more grand-scale and theatrical. Monsters start to come out.

We got a little taste of the Joker last season. What are your plans for him this year?

Danny Cannon: Well, he's in Arkham, if that is in fact the Joker. He is in Arkham, where Barbara Kean is put in the first episode, also. It's in the wing of Arkham where the worst of the worst are kept. An event happens which allows him to be involved in the next few episodes.

Heller: He gets to fulfill his destiny in a very grand way.

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Which villains will be rising up in Season Two?

Cannon: We thought long and hard about this. So many of the characters don't have origin stories. It's not just a question of enjoying going back to an origin story. It's, "Who fits in a realistic world?" They have to have their feet on the ground. Some characters are a little more advanced, stylistically. We found the Mr. Freeze story very emotional. That's one we are going to look at. Hugo Strange is a very interesting character who has never had an origin story, as is the Calendar Man. Azrael is a character we are starting very, very, very way back. Tigress, also.

Where does Lucius Fox fit in this season?

Again, we are starting to explain how Lucius Fox and Bruce Wayne got to be so tight. How did Lucius come into his life? What was his role in Wayne Enterprises and his relationship with Bruce's father? He's instrumental in unlocking some of the secrets in what will later become the Batcave, which is now just his father's secret office.

Knowing how Barbara and [Jim] Gordon's relationship ends in the comics, how do you approach that on the show?

Heller: That is one of those odd things about doing a show which has a future already mapped out for it. You have to try and be true to that, but come up with twists on stuff. If you just tell people what they already know about those characters and those events -- there's a certain fun to that, but we are always trying to find a different angle on the secret. We are going to tell you the secrets that your parents don't tell you until you open the door after they are dead and discover, "Oh, my God!" It's that kind of stuff that we will be revealing about those relationships.

"Gotham" features a large ensemble cast, and you are dealing with a lot of different stories. Did you decide to service all of them over the first three-episode arc, or how is that happening?

Heller: One thing is, the world is so vast. There are so many storylines and characters and situations you can portray, you can overstuff yourself. What we've always criticized ourselves for, that first season, which is a comic book thing, is you can stuff more into a comic book world than you can into a classical drama.

But this season, we're much more concerned with telling coherent arcs than -- it's also partially the luxury of having a full order and knowing how many we are going to do. We started out with a notion that we would have a procedural element. Frankly, the world is too antic for that kind of formal structure. Every episode has to go where the characters and story take it, so, every episode is going to be different. Every episode is going to have its own energy and pop.

"Gotham" returns to Fox Monday, Sept. 21.