Joss Whedon on Writing 'Avengers 2': 'Enormous Fun, Followed by Deep Panic' (Video)

At the MTV Movie Awards on Sunday, Joss Whedon was reunited with some of the stars of The Avengers onstage when the film won for best fight. The writer-director took the stage with Tom Hiddleston, Samuel L. Jackson and Chris Evans to accept the award.

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Whedon already is hard at work on the sequel to the superhero ensemble film. On the red carpet before the show, he noted that he's nearly done with the first draft.

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"It's been enormous fun, followed by deep, deep panic," Whedon tells THR. "I'm in the deep panic stage now. Actually, I've gone past panic into a vague nether-stage."

Whedon says that because he did the "meet and greet" in the first film, which starred Robert Downey Jr., Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner and Hiddleston, he can "really slam them together and beat them up and figure out what makes them tick."

The Avengers, which hit theaters May 4, 2012, became the top film of 2012 at the box office, grossing more than $1.5 billion worldwide. Whedon was confirmed to write and direct the sequel in August. It's scheduled to hit theaters in summer 2015.

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Whedon spoke to THR about his decision to take on a sequel.

"I sat down and thought about it, 'Do I have a story to tell?' Same thing I thought before the first one. ... It took me 40 minutes to realize not only did I have a story, but I was in love with it."

While the plot of the sequel has been kept secret, Whedon did give THR a hint about what the Avengers could be up against in the film.

"Themselves," he says. "We're all our own worst enemy."

Watch THR's interview with Whedon above.

Email: Rebecca.Ford@thr.com; Twitter: @Beccamford