Director Clint Eastwood is pulling double duty this year, debuting American Sniper in theaters this Christmas just six months after Jersey Boys enjoyed success at the box office this summer. The first images have arrived, giving us a look at Bradley Cooper as Navy SEAL Chris Kyle and Sienna Miller as his wife Taya Renae Kyle.

American Sniper is based on Chris Kyle's best-selling 2012 memoir. The man is known as the most lethal Sniper in American military history. While Bradley Cooper didn't get to meet with Chris Kyle, he does explain that he talked with him on the phone:

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"Thank God I got to talk to him once on the phone. It was a very quick conversation. But I did tell him how serious I was about making this movie. And he should just know that whatever fears he had about Hollywood, to just put them aside and trust me. That I was going to do everything I could to tell this story."

Shortly after this phone call, Chris Kyle and a companion were shot and killed at a shooting range in Texas February of 2013. A troubled Marine veteran is now on trial for the murder. With the subject of his movie now gone, Bradley Cooper made a vow to keep his promise to the fallen soldier.

"I had to do right by him and his family, there was really no choice. You're sitting across the dining-room table talking to this person's father and mother. And his children and wife are there. And he's passed away. Knowing that they are putting all of their stories in your hands and the responsibly of that, it's actually unique."

You can check out Bradley Cooper's transformation into Chris Kyle in the following photos, which required the actor to undergo a rigorous diet and workout regimen. You can read more from Bradley Cooper: CLICK HERE

American Sniper Photo 1
American Sniper Photo 2