'Avengers': Captain America, Thor Fight In Fan Footage (VIDEO)

They swooped in to save the day -- and make major box office cash -- this summer, and now, Captain America and Thor are teaming up.

Following their successful big screen launches, the two heroes will feature in the Marvel comics teamup next summer, Joss Whedon's massive "Avengers" flick. Played by Chris Evans and Chris Hemsworth, respectively, they join up with Robert Downey, Jr.'s Iron Man, Samuel L. Jackson's Nick Fury, Mark Ruffalo's Incredible Hulk, Jeremy Renner's Hawkeye and Scarlett Johansson's Black Widow to form the greatest -- and star-studded -- superhero squad in film history.

Shooting in locations throughout the country, the cast is currently in Cleveland, where they're wreaking havoc on the city's streets and putting together some major action scenes. A fan caught some of the fight scenes on a hand-held camera, and posted some semi-spoiler footage, which can be seen below. Also check out the teaser trailer that came at the end of "Captain America" last month by clicking here.