The cast and creators of ABC's Marvel's Agents of SHIELD previewed the network's big fall swing, fielding questions during their time at the Television Critics Association's summer press tour about the show's procedural nature, Joss Whedon's involvement and the mysteries behind Agent Coulson's survival.

The pilot, which was screened Sunday afternoon at TCA following July's Comic-Con debut, marked the first time many of the assembled critics and reporters had screened the drama as Marvel -- as it did during development and pilot season -- continues to keep plot details under wraps.

PHOTOS: The Scene at Comic-Con 2013

SHIELD is based on Marvel Comics' secret intelligence organization that has appeared in countless titles including Iron Man, Captain America and The Ultimates since being introduced in the 1960s. The military law-enforcement agency's moniker stands for Strategic Homeland Intervention Enforcement and Logistics Division, which has also evolved over time in the comics.

The series, in a way, picks up where Marvel and Whedon's big-screen movie The Avengers left off and features Clark Gregg's Agent Phil Coulson's mysterious return after having been killed off in Whedon's film. How I Met Your Mother's Cobie Smulders reprises her role as Agent Maria Hill in the pilot.

Here are the big burning questions that were answered during the session.

How much synergy will there be to use SHIELD to promote the upcoming sequels of Thor and Captain America?

"There will be as much as we can allow," Whedon said. "We're still working that out. It's a fluid process. It's a fun opportunity, but it's not the reason for the show. It's not an Easter egg farm, we want people to come back." The prolific showrunner noted that the series has to work for those who haven't seen The Avengers or any of the Marvel universe movies. He stressed that SHIELD is about the characters and that he hoped that viewers would become invested in them.

How big can the pilot be?

Marvel's Jeff Bell said the glossy pilot -- which includes slick sets and a number of visual effects -- "looks bigger than you think" the production spent on it. He praised Marvel and ABC's generosity with the production values. "We have a production team telling us what we can and can't do; Marvel and ABC have been very generous with us. We have a responsibility to Marvel to look awesome and terrific," he said, stressing that the focus will be on the characters first and foremost rather than VFX.

How much creative freedom does Whedon have with SHIELD?

Whedon, who wrote and directed The Avengers and whose credits also include Buffy the Vampire Slayer, Firefly and Dollhouse, said he's gotten something very different than what he's received in the past. "We've gotten trust, which is different than freedom. My collaboration with Marvel on the movie was extraordinary and unprecedented," he said, noting both ABC and Marvel have been very involved with the vision for the show. "They're very supportive of the vision we first laid out. We're all trying to make the same show. We're all on the same page, which has occasionally not happened to me," he said with a nod to Firefly.

PHOTOS: ABC's 2013-14 Season: 'S.H.I.E.L.D.,' 'Once Upon a Time in Wonderland,' More

How big of an involvement will Whedon have?

"As much as an exec producer can who is also making a movie," said Whedon, who is already signed on for The Avengers sequel. "I got the best writers and actors I could so I could do this and that's the best way to run a show."

How accessible will it be for non-Avengers viewers?

The pilot is equal parts Avengers follow-up and procedural, with a clear superhero case-of-the-week format established in the opening episode. "We wanted to make sure there's an investment in the characters as much as case of the week," Whedon said. He added that ABC and Marvel asked him to make sure that there would be elements to the show's recurring story and a conclusion to the case of the week. "Every week it's not going to be some new hero," he continued. "There could be a device, a mystery. There's so many aspects as to what's happened since everybody in the world found out there's a superhero team and aliens invaded New York. We want to be able to change it up every week -- spy stuff, hero stuff, heartfelt stuff. [We want to make sure] that every week you get something that feels different so it's not turkey every day."

How many Marvel references will be packed into the series?

"I don't think we'll make references for the sake of making them," EP Maurissa Tancharoen previewed of the show's approach to adding comic book references. Bell noted that if there was an opportunity to name a character after someone that exists in the massive Marvel universe that doubles as a way to be inclusive, they won't shy away from doing it.

Is SHIELD just for fanboys?

Marvel EP Jeph Loeb and Bell stressed that with Marvel's first TV show, the producers wanted to appeal not just to its core fan base but "hit it out of the park" the way in which The Avengers did on the big screen. "[The Avengers isn't] a movie for one group of people; that's a movie for everyone," he said. "Iron Man 3 has the same feeling. Whether ABC or the Marvel audience, our hope is that everyone watching TV at 8 p.m. on Tuesday is watching our show." Added Bell: "We hope this is big and broad enough for everybody but [there are] specific things people can find and identify with."

How are they handling the pressure to deliver for ABC?

The cast and creators didn't seem to be phased at all when asked about the pressure to deliver for ABC. ABC is rebuilding Tuesday nights on the back of SHIELD, which will serve as a lead-in for fellow rookies The Goldbergs, Trophy Wife and Lucky 7. "If we think about that all the time we'd never make any decisions," EP Jed Whedon said, noting he, wife Tancharoen and Joss Whedon will use the same approach for SHIELD that they did with web series Dr. Horrible's Sing-Along Blog. "We try to keep it fun and tell stories we want to see." For his part, Gregg said he wasn't aware of any pressure at all as he shows up to work every day. "ABC is going to have to take care of itself," he added.

Is Coulson an LMD (life model decoy)?

Loeb dodged questions about if Gregg's revived Agent Coulson is really a robot. "That's a Level 7 question, we can't really declassify that," he said with a nod to the pilot. Clarified Whedon: "We will be dealing with the issue, that is part of the thread of the story."

Could J. August Richards return?

"I thought he was great, too, so do that math," Joss Whedon said of the character who is the focus of SHIELD's first mission in the pilot.

Will Whedon look to return to TV with his own property after SHIELD?

"The goal is never about the medium, it's always about the next story; what I haven't done before, learning more, becoming better and whatever story grabs a hold of me," he said. "Sometimes I don't know what medium is best for that. … I like not knowing what's next. It's all about making people care about people."

SHIELD premieres Tuesday, Sept. 24 on ABC.

E-mail: Lesley.Goldberg@THR.com

Twitter: @Snoodit