SAN DIEGO — Fans expecting to see a snippet of the new "Marvel's Agents of S.H.I.E.L.D." television show Friday at Comic-Con got a surprise instead — the chance to see the entire debut episode.

Thousands of fans went wild when Marvel executive Jeph Loeb and series creator Joss Whedon surprised them with the episode, which features Clark Gregg as Agent Coulson, the S.H.I.E.L.D. agent everyone thought died in Marvel's recent blockbuster film "The Avengers."

"I've got to say it's a little hot in here," Loeb said, taking off an over shirt to reveal a T-shirt with the words "Coulson Lives" on the back. The crowd started chanting "Coulson! Coulson! Coulson!"

That was just the beginning of the cheers, laughs and even tears — from Gregg, who got choked up when talking about the chance to return to the Marvel universe after appearing to die in a key moment in "The Avengers."

"I'm a longtime Marvel fan and I can't believe this is happening to me," Gregg said as he got a little misty after hugging Whedon for an uncomfortably long period of time. "I didn't like being dead, but I really liked my death. And then I met Lola."

"Lola" is Agent Coulson's suped-up red Stingray Corvette that's not quite as vintage as it looks.

Without revealing too many details to ruin the debut for fans not at Comic-Con, the show follows Coulson as he builds a team of fellow agents to deal with the growing problem created in a world quickly changing because of superheroes and their foes, alien visitors and Norse god appearances.

Fast-paced and full of comic moments that don't always require a deep knowledge of comic books, the episode laid the groundwork for the series with several subplots that will play out over time. Until Friday, little had been revealed about the ABC show set to debut Sept. 24.

Most of the show's cast attended, including Ming-Na Wen (Agent Melinda May), Chloe Bennett (Skye), Iain De Caestecker (Agent Leo Fitz), Elizabeth Henstridge (Agent Jemma Simmons) and Brett Dalton (Agent Grant Ward). Dalton got a wolf whistle from the crowd, leading to laughter.

"Yeah, we've got a really unattractive cast," Loeb joked.