Semper grew up on half-hour dramas, which told serious stories in under 30 minutes, and took that model to Spider-Man.

"I wanted there to be a real, serious underpinning to the show," Semper told the crowd at Comikaze Expo in downtown Los Angeles.

But here's the big news: Semper revealed that the cast (including J. Jonah Jameson himself, Ed Asner) has agreed to reunite for an upcoming project they plan on using crowdfunding to finance. The animated project, titled Rocket Men, would harken back to retro-pulp style of something like The Rocketeer.

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Spider-Man ran for five seasons from 1994 to 1998 on Fox and was groundbreaking at the time — treating the material seriously (sometimes to the point of melodrama) and getting stellar performances from its sprawling voice cast. While Batman: The Animated Series earned more acclaim (it won four Emmys), Spider-Man more than holds its own 20 years later. The series managed to open up the Marvel Universe, deftly talking on storylines as personal as Spidey's battles with Harry Osborn and as vast as the Secret Wars. Many fans consider it the definitive animated incarnation of the wall crawler.

The panel started with a sizzle reel showcasing some of the stars' best work. It was a proud moment for the cast, some of whom hadn't seen the clips in years or decades. This clip, in which Mary Jane's clone dies, had Saratoga Ballantine (Mary Jane) almost in tears, she said.

The other actors — Christopher Daniel Barnes (Spider-Man), Jennifer Hale (Felicia Hardy), Gary Imhoff (Harry Osborn), Rodney Saulsberry (Robbie Robertson), Gregg Berger (Mysterio and Kraven the Hunter) and Patrick Labyorteaux (Flash Thompson) — said one thing that made the show special was that they recorded their parts together in the studio, something that rarely happens with voiceover work these days.

"It was like a radio show. We were all in the booth together, and we were all interacting with each other. And you feed off of that," said Barnes, who also called playing Spider-Man a big responsibility.

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"You are the current avatar of this Marvel deity. This is our Iliad. This is our Odyssey," Barnes said. "It touches something universal in us. When you get the chance to be the voice of that character, that means something."

While Ballantine got big applause for reciting her iconic Mary Jane line ("Face it Tiger, you just hit the jackpot"), the biggest cheers went to a pretaped video message from Asner, who reprised his role as J. Jonah Jameson. Asner's Jameson couldn't understand why everyone was wasting time talking about a TV show — he'd rather be at Spider-Man's funeral.

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Taking fan questions, Semper said the series finale was meant to be a happy one that also had the potential to keep going. The 1998 episode ended with Spider-Man going off to find Mary Jane, who had been lost in another dimension.

"I knew that we were finished with 65 episodes, but I thought maybe we'd have a little bit longer. I thought I made it very clear at at the very end that he was going to get to Mary Jane, but apparently I traumatized all of you. So I apologize for that," Semper joked. "I was leaving that door open in case by some miracle they said we were going to do a few more. "

Stay tuned for more from Spider-Man in the coming year. Semper will be posting updates on this Facebook page, as well as on this website. He's also got a series of podcasts planned. Listen to the first below.

Email: Aaron.Couch@THR.com

Twitter: @AaronCouch