Comes out on Christmas Day. Directed by Clint Eastwood, starring Bradley Cooper. From the trailer it seems that Cooper nailed Chris's demeanor.
Cooper told USA Today that he only had one opportunity to speak to Kyle, a brief phone conversation where the actor promised to do everything he could to tell this story faithfully, before the Navy SEAL was murdered by a troubled Marine veteran while practicing at a Texas shooting range. The shocking turn of events added pressurized the already delicate adaptation. "I had to do right by him and his family, there was really no choice," Cooper told the paper. "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."
As evidenced in the trailer, Cooper's doing his part to realistically portray the fallen soldier. According to the same interview, the actor put on 40 pounds and trained with the same Navy SEALs who worked with Kyle, including Kevin "Dauber" Lacz, Kyle's sniper partner during his last two tours (he also served as a technical adviser and portrays himself in the movie).