Jake Gyllenhaal has revealed that he witnessed a murder while he was preparing for his new movie End of Watch.
End Of Watch sees Gyllenhaal take on the role of a cop and he rode with the LAPD in preparation for the movie.
The actor was shown a world of violence and crime and he admits that working on this film has opened his eyes and changed his life.
Speaking to Hitfix the actor said: "This movie changed my life. I mean, the experience of it... every step along the way I learned something about myself. And I saw the world in a different way."
"The first ride I went on I saw someone murdered. It changes your life. You don't come back from something like that and not see the world a different way.
"And subsequently, [watching] everything from domestic violence to stolen cars to you name it.
"And along with the camaraderie and the friendship and the joking and all of that, seeing that for real for five months and shooting for 22 days? And seeing it for real? I won't be the same in many, many good ways."
End Of Watch is the first movie for Gyllenhaal since Source Code as he teams up with Michael Pena and director David Ayer.
The movie will play at the London Film Festival next month where it will be in competition.
End Of Watch is released 23rd November.