Cast list for 'The Avengers' announced

Joss Whedon has announced the cast for 'The Avengers'.

The director took to the stage at the Comic-Con event in San Diego on Saturday, to show the crowd the entire principal cast for the comic book-adaptation movie, including Samuel L. Jackson, Scarlett Johansson, Chris Hemsworth, Chris Evans, Clark Gregg, Robert Downey Jr., Mark Ruffalo, Natalie Portman and Jeremy Renner.

Whedon told MTV News: "The energy is extraordinary. This is an extremely collaborative, supportive intelligent cast; they're very sweet.

"They're not challenging each other, they're just enjoying each other and ready to get into it. And that's an exciting atmosphere.

"I even said: 'Don't do it if we can't make the deal with these actors.'

"I desperately wanted this exact crew for the movie and we didn't know until Saturday morning that it was going to happen, and that's because of the extraordinarily hard work and trust from people who aren't me."

Chris Evans will be playing Captain America, Chris Hemsworth will be playing Thor and Robert Downey Jr. will be playing Iron Man, roles they have already signed up for in separate movies.

Little is known about the plot of the movie, which is due for release in summer 2012.