The Justice League returns to Cartoon Network this Fall in a new quarter-hour animated series, but fans at Comic-Con International in San Diego got an early look at the upcoming show from Warner Bros. Animation. Producers Alan Burnett, Butch Lukic, and Jim Krieg, voice actors Kevin Conroy and Diedrich Bader, and character designer Shane Glines were on hand to answer fan questions and reveal the pilot episode of "Justice League Action." IGN's Eric Goldman moderated the panel.

The panel began with a screening of the debut episode of "Justice League Action."

The show opens with Superman and Wonder Woman fighting off giant toys -- dinosaurs and stuffed animals respectively, while batman takes out some flyers. Meanwhile, Cyborg sits on the couch playing video games.

"Aren't you supposed to be guarding the tower?" Superman asks.

No surprise, the villain behind it all is Toyman, who arrives on the scene to subdue the heroes -- and transport them into a video game. Batman seems oddly familiar with it...

"Robin plays it all the time."

Cyborg makes his comrades a bit uncomfortable with how much he's into the Toyman's scheme. He ends up playing against Toyman in a "Street FIghter"-esque match, gets some more awkward looks when he doesn't want to choose Batman as his fighter because "he doesn't have any powers."

Signing off the episode description, we'll be back for the panelists!

A preview also showed characters like Firestorm, Luthor, Dex-Starr, Hawkman, Lobo, Brainiac, Grundy, Plastic Man, Vixen, Mr Freese, Booster Gold, and more.

Krieg described the show as taking "characters who can be super serious but can be put in ridiculous situations," as well as the reverse for characters like Plastic Man. "The threat is always real, but there may be a left turn in it," he said.

Lukic said the pilot "pretty much encapsulates what the show is" but has more humor than a lot of episodes, which he said are more action oriented. "Nothing as dark as what's going on [in other media] in the DC Universe," he said.

Glines said that, when designing characters, he started from the idea of Bruce Timm's iconic designs and built from there.

"Part of my challenge in my 25 years playing the character," Conroy said of voicing Batman, "is keeping it consistent and keeping it fresh." From "TAS" to the "Arkham" games, Conroy said that the important thing is consistently.

"He's a character that's dark, but he's so dark, that if you twist it a little, it's very funny," he said, which comes in handy for lighter situations.

Bader said he was given "a lot of rope" for Booster Gold. "So I made him French," he joked. "I'm actually going to change countries every episode. The Slovenia one is a lot of fun."

"Booster really looks up to Batman," Bader said, describing it as "hero/father relationship." "It actually hurts him when Batman criticizes him and calls him a child -- he is a child, but it still hurts to hear him call him that."

Burnett said the opening scenes would typically be "action-packed," and viewers would find out shortly thereafter how the heroes got into the situation.

"All the things I couldn't do on 'Superfriends,' I could do on this show," Burnett said of his long career in animation.

"JL Action" will allow for unusual pairings of heroes, which Lukic said "feels right" for the series and is a departure from "Unlimited," which focused on the core seven Leaguers.

Of Mark Hammill, Conroy said, "I wish people could see him, what he does when he's in the booth." "He becomes the Joker," Conroy said.

"He's a generous actor," Conroy added. "He knows that the more you give, the more you'll get. He gives me so much in recording, which inspires me to give so much more back."

Conroy compared his acting relationship with Hammill to friends who haven't seen each other in a while picking up where they left off. "There's no catch-up time."

Bader joked that he merely "played" Batman on "Brave and the Bold," while Conroy is Batman. Like "Brave and the Bold," though, Bader likes that "Action" will feature many less well-known characters from throughout the DC Universe.

Patton Oswalt will play Space Cabbie, Lukic said, and Krieg said that Hannibal Buress will play Mr. Terrific. "He's terrific -- I wasn't even set up for that joke!"

Asked about musical numbers or a full episode, Conroy joked that, "Oh yes, I can guarantee Batman will have many musical numbers." Unfortunately, he confirmed he was, in fact, joking.

A fan asked about Ted Kord, but Krieg said he does not appear in season one. "He can appear in season two, when you demand him in season two, when you demand that there be a season two."

Asked about the "JLU" episode in which Batman sings "Am I Blue." He sang a bit, then said that voice director Andrea Romano "knows I love to sing," and set up a situation where it would make sense.

A fan asked "what it would sound like if both Batmen had lunch together."

Conroy: "I'm gonna have a roast beef on rye."

Bader: "I don't know if you should order that."

Lukic said "there currently is no Robin on the show," but would probably appear in a second season.