Jake Gyllenhaal has revealed the bond between him and Michael Pena in new film End Of Watch is real.
The Brokeback Mountain star and Michael play patrol cop partners in the movie - written and directed by former US Navy serviceman David Ayer - and they worked hard for months to build up a strong working relationship.
Jake said: "I spent five months preparing for the movie together with Michael for a 22-day shoot, which is the shortest movie shoot I did in my career.
"We had not worked together before this movie, but five months together was enough to create a real friendship. We spent almost every day together. We did tactical training with live ammunition, we did ride-alongs with LAPD (Los Angeles Police Department). We did fight training and sparring five days a week in a dojo, and in between we were rehearsing the scenes - each one we did over 100 times each. And after five months we actually became real friends."
The Donnie Darko star insisted the film would not have worked without his friendship with Michael.
Jake said: "What sets it apart from all of the other cop genres that we've seen in so many mediums is the real friendship between these two guys and the fact that their relationship is potentially threatened.
"End Of Watch doesn't exist without the bond between them. I've been in films where my character drives the whole movie, and is required to carry every scene. This film is different. We're two pieces of a whole, and this doesn't work without either one of us."
:: End Of Watch opens in cinemas on Friday, November 23