“What we are doing here is completely unprecedented,” Joss Whedon explains in ‘The Ultimate Protection,’ a new behind-the-scenes clip that delves into the history of ‘The Avengers.’ “Marvel is taking the characters that they are putting into their movies and bringing them all together in a team, franchise experience, which really has never been done before.”

He’s right. And that’s part of the reason why we are beyond excited for ‘The Avengers,’ which – as you likely know – kicks off Summer 2012 on May 4 with the merging of various super powers into one dysfunctional family.

The new clip, apparently brought to us by Norton Antivirus software, traces the history of these characters on screen, emphasizing the four key figures in the building of The Avengers: Iron Man (Robert Downey Jr.); The Hulk (Mark Ruffalo); Thor (Chris Hemsworth); and Captain America (Chris Evans).

Whedon and Marvel President Kevin Feige also emphasize the importance of New York City to the franchise, and the Marvel, as a whole. Of course, Whedon’s standing in the rubble of what we assume is midtown Manhattan, so they pay the Big Apple back by reducing it to dust.

‘The Avengers’ opens May 4, bringing together a multi-year collaboration between various films in order to realize a massive vision on screen. Will it work? In Whedon we trust. In the meantime, use this featurette as an appetizer, and a sprint through recent Marvel history, to remind yourself how we got to this spot … and where we might be going next.