Warner Bros
February 18, 2015 4:14 PM EST

Answer by Jason Hall, Screenwriter of American Sniper, on Quora.

Chris Kyle’s book didn’t fully encompass who he was. It was written at the time when he had just gotten back from war. He was angry, dissolute and fractured, in many ways, by these four tours of duty that he had done. It was the close to a decade of war and training for it that had consumed him. The book was dictated in a couple of weeks after that time.

There were lots of questions that the book asked, but didn’t answer like who this guy was, who he was before, and who he would become. There was a lot of anger in the book. I had met Chris, and I knew the book wasn’t a full picture of the man. So the challenge was finding out who he was, and what the sacrifices he made entailed. There was a lot of stress. You could read it in between the lines of the book, but it wasn’t fully explored in the narrative. That was my challenge — to get the full picture of the man. I did it the best I could with him when he was alive. I got a lot from him, and I also got to witness the change and softening that occurred in him over the couple of years before his murder. We got to become friends and the laughter started to come back. This is what happens with warriors — sometimes they find their way back and sometimes they don’t. But I was witnessing him finding his way back.

After his murder, his wife folded me into the fuller picture of his story. She was able to articulate the things that men sometimes don’t tell other men. She talked about who he was before the war, what a big heart he had, how gentle he was with her, and how he walked her out of the darkness and into the light. That story from her took on a narrative and painted a fuller picture of this man and what his sacrifice had been with this war. She also painted a picture of what it was like for him to come back, how he found his way back in the months before his death, fully returning in her eyes. The story she told was: months before he was murdered, Chris walked into the kitchen and she looked at him and realized that for the first time since he had been home, her husband was finally home.

This question originally appeared on Quora: What are the challenges when adapting a book into a movie/tv show?

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