Gyllenhaal is a free-wheeling actor

Jake Gyllenhaal as Tommy Cahill is the feisty younger brother, a drifter who has just got out of jail and hits on Grace (Natalie Portman) in Jim Sheridan's drama "Brothers".

"Brothers" - The Truth videoclip, featuring Tobey Maguire and Natalie Portman.

"Where the movie lives and dies is in the relationship between the two brothers" says Sheridan, who says Maguire and Gyllenhaal deliver in roles that are more grown-up than what they customarily play.

To look convincing as a prisoner of war, Maguire dropped 25 pounds from his already thin frame.
"He is a vegan, so as far as I am concerned he doesn't eat anyway. He ate less vegan," said Sheridan, who worries about Maguire's extreme diet having a long-term effect.

As an actor "Tobey likes to control a lot. That is the way he lives. He has a cook that cooks for him. His world is very controlled. Even when acting, he is not the kind of guy who would get loose. He's quiet and pensive and thinking about things."
By contrast, Gyllenhaal is a "free-wheeling actor. He is always looking around. He has three or four things going through his head, and normal stars just have one."

It would mean trouble, Sheridan believes, if a director told Gyllenhaal to just stand there and hit his mark. "The way he lives in a scene is to be half there and half out there looking around. I found it completely fascinating."