By Samantha Simon
Updated Dec 27, 2014 @ 10:12 am
Each product we feature has been independently selected and reviewed by our editorial team. If you make a purchase using the links included, we may earn commission.

With a title like American Sniper, you better believe that Clint Eastwood’s latest film is going to bring the action. The drama---in limited theaters now---follows the story of the late Chris Kyle (Bradley Cooper), the U.S military's deadliest sniper of all time. Based on Kyle's autobiography, the movie depicts his four tours in Iraq and the difficulties he faces upon eventually returning home.

“The film shows the effects that being in war has on somebody and the people around them,” Shameless's Jake McDorman, who portrays a Navy SEAL alongside Cooper in the movie, told InStyle when he stopped by our offices the week of the film’s New York City premiere.

Cooper, who also produced the film, is almost unrecognizable in the lead role. “He really went all out and put on, like, 45 pounds,” said McDorman. And we’re not just talking the actor’s usual buff self. “He’s been ripped before, but this time it looked like somebody ate Bradley Cooper—he’s just this big monster.”

Looking the part was only half the battle. In order to believably portray seasoned snipers, the actors trained for five days when they first arrived on set in Morocco. “We had to get acquainted with the gear and learn how to hold a gun and shoot,” said McDorman.

On hand to help: Kevin “Dauber” Lacz, who served with Kyle on Navy SEAL Team 3. “He was just supposed to be the technical advisor and help Bradley,” McDorman said. But, after Eastwood had Dauber audition to play the role of himself (yes, really), he landed the part—to McDorman’s relief. “If he had just been the technical advisor I would have been scared s***less, because it would have been like a teacher looking over your shoulder during a test."

Dauber wasn’t the only one setting an example on set. “I learned a lot from Bradley,” McDorman said. No matter how heavy the material, “He never strayed away from who Chris was as a person,” McDorman said. “Every scene you were in with him was so real, because he comes to every scene so present.”

Check out the below trailer for American Sniper, in limited theaters now and playing everywhere Jan. 16.