The 30-year-old actor has been cast in the new biopic based on Sergeant Adam Schumann, who is trying to adjust to civilian life after he returns home from the war in Iraq, and the dark-haired star has admitted he has never had to deal with a film where he had to ask «many questions» to help prepare him for the role as he did with his latest project.
Speaking to Collider about his latest venture, he said: «For me, I never dealt with a movie to where I needed to ask as many questions as I did for this movie.
«You can’t relate. You really can’t. Either you’ve been to war or you haven’t. There was really nothing, I’ve experienced trauma and could relate on that level.
«But on the day to day, doing that job as a sergeant in the military, I had absolutely no foundation for it.»
The new film by Jason Hall is based on the memoirs of the soldier, and follows Sergeant Schumann, as well as other soldiers, on their journey to physical and emotional rehabilitation.
In order to prepare for the role Teller met with Schumann, as well as other people suffering from post-traumatic stress disorder (PTSD), to educate him learn about the condition and to help him give an honest portrayal.
He said: «I read a lot of books on it and that gave me an introduction to Adam and post-traumatic stress disorder.
«[I also was] hanging around the guys. I learnt the most being around them and those who have lived through it.
«I certainly felt a lot of empathy. I am not a journalist but that empathy lead me to ask questions.»
Teller stars alongside Cecil M. Henry, Hayley Bennett and Scott Haze in the forthcoming production.