"Brothers" tells the powerful story of two siblings, thirty-something Captain Sam Cahill (Tobey Maguire) and younger brother Tommy Cahill (Jake Gyllenhaal), who are polar opposites. A Marine about to embark on his fourth tour of duty, Sam is a steadfast family man married to his high school sweetheart, the aptly named Grace (Natalie Portman), with whom he has two young daughters. Tommy, his charismatic younger brother, is a drifter just out of jail who’s always gotten by on wit and charm.