'Transformers 3' Director Michael Bay Talks 'Alien Attack' Scene

'Something very bad has happened to America — and this is at the end of the movie,' director reveals of scenes being shot in Chicago.

Michael Bay has been utterly destroying Chicago, blowing up cars, demolishing streets, leaving mangled steel and crumbled concrete across entire blocks. That's just what it's going to take to make "Transformers 3" a kick-ass flick and erase from our memories last year's decidedly so-so second installment in the franchise.

In a new interview with the Chicago Sun-Times, Bay revealed just how the Chicago footage will fit into the new movie. The sequence, he said, "comes at the very end of the movie and the city is under alien attack, so it's very critical and important to the film's climax."

While overall plot details remain tightly guarded, we do know the film dives into the space race between the United States and Soviet-era Russia. The Transformers are rumored to play an integral part in the nations' battle for the stars.

On Monday, Bay took over an area between Michigan Avenue and Wabash Avenue for a scene that focused on the military's response to the alien attack. "[There are] a number of base jumpers who are part of [co-star] Josh Duhamel's unit," Bay explained. "The heroes in this movie have very few people coming to help them this time. I like to think of it as the 'Black Hawk Down' version of 'Transformers' — it's much more intimate in terms of what's happening.

"Something very bad has happened to America — and this is at the very end of the movie," he added.

The production is expected to stay in Chicago until the end of August, at which point it moves on to Detroit, Los Angeles, Washington, D.C., and Florida, as well as a number of international locations that producers have not yet revealed. Wherever they travel, through, expect the gunfire to be loud and the explosions to be big.

"I do love action, but all that action and those explosions only work if they support the script," Bay said.

Check out everything we've got on "Transformers 3."

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