The 41-year-old did his own stunts in the movie, and admits swimming in water was the toughest challenge.u00a0"For all the stunts I was well prepared. But the water? Below 32 degrees? There was nothing I could do to prepare for that. And it freaked me out. Let's just say it wasn't very pleasant," Glamour magazine quoted Renner as saying.

However, the actor found the action scenes in the movie a piece of cake.u00a0"Those scenes are like a well-oiled machine because they have to be smooth, fast and vicious. Of course, if you're doing hand-to-hand stuff, there are going to be black eyes. I had to give a few," he said.