For those of you living under a rock, the world premiere of The Avengers took place last night.  We rounded up a few of the positive Twitter reactions and some images from the premiere earlier today, but now some goodies are online to appease us fans that weren’t lucky enough to catch the film last night.  In addition to a new featurette that features writer/director Joss Whedon talking about the film, 20 minutes of behind-the-scenes footage is now online.  We get a fun look at all the actors pretending like they’re superheroes, and there’s even some footage of Mark Ruffalo getting his Hulk on.Hit the jump to check out the videos.  The film stars Robert Downey Jr., Chris Evans, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Tom Hiddleston, and Clark Gregg.  The Avengers opens in 3D on May 4th.Image via CBM.  Click for hi-res.the-avengers-hulk-imageHere's the 20 minutes of behind-the-scenes footage (also called B-Roll).The featurette comes by way of IGN.Here’s the official synopsis for The Avengers:

Marvel Studios presents in association with Paramount Pictures “Marvel’s The Avengers”–the Super Hero team up of a lifetime, featuring iconic Marvel Super Heroes Iron Man, The Incredible Hulk, Thor, Captain America, Hawkeye and Black Widow. When an unexpected enemy emerges that threatens global safety and security, Nick Fury, Director of the international peacekeeping agency known as S.H.I.E.L.D., finds himself in need of a team to pull the world back from the brink of disaster. Spanning the globe, a daring recruitment effort begins. Starring Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner and Samuel L. Jackson, and directed by Joss Whedon, “Marvel’s The Avengers” is based on the ever-popular Marvel comic book series “The Avengers,” first published in 1963 and a comics institution ever since. Prepare yourself for an exciting event movie, packed with action and spectacular special effects, when “Marvel’s The Avengers” assemble in summer 2012. In “Marvel’s The Avengers,” superheroes team up to pull the world back from the brink of disaster when an unexpected enemy threatens global security.