Taking the good-son, bad-son story in a different direction (one that runs through Afghanistan), "Brothers" is a powerful statement on loyalty, love and the cost of war.

Director Jim Sheridan's take on the film (a remake of Susanne Bier's original) sifts through the effects of war on one family — a family that didn't need any outside influence to add to its problems.

Sam Cahill (Tobey Maguire) is a Marine Corps captain about to ship out to Afghanistan — again. His wife, Grace (Natalie Portman) and girls (Bailee Madison and Carey Mulligan) are used to the drill, though that doesn't mean they're happy about it. Before he goes, Sam has to run an errand: Pick up his brother Tommy (Jake Gyllenhaal), just released from prison.

The lines are drawn that starkly. Sam is a hero; his father, a former Marine (Sam Shepard), reminds Tommy more than once. And what is Tommy, exactly? The town screw-up, pretty much, one of those guys who hangs around and never amounts to much.

Then, the unthinkable: Bereavement officers show up at Grace's door. Sam has been killed in an attack on his helicopter.

We know differently. Sheridan moves back and forth between Afghanistan and the Cahill's home; Sam has actually been captured and is being held prisoner with a fellow Marine (Patrick Flueger). Their situation is dire at best, but at least they're still alive, for now.

Grace doesn't know this, of course. She is learning to live as a single mother. Help comes from a most unlikely place: Tommy. Whatever his life has been missing (such as a decent relationship with his father), Grace and her daughters seem to provide. He and Grace grow close, and the girls love having him around.

In Afghanistan, meanwhile, Sam is forced to make a horrible, torturous choice. And then, miraculously, he's freed. Grace and the girls are elated, of course. So is Tommy. So is everyone.

But something's wrong. Sam isn't the same. We know he's haunted by guilt.

It eats at him constantly. And he is wracked by jealousy, convinced that Tommy and Grace had an affair.

To see Sam disintegrate is unnerving. To see his girls watch it happen is heartbreaking. They don't understand what's happened, of course — no one does. Sam won't say, and it's killing him. They only know it's a lot happier when Uncle Tommy is around.

Portman is excellent as a woman quietly navigating a wrenching set of circumstances. Grace loves Sam, but she doesn't know how to help him.

Gyllenhaal is also outstanding as a man adrift finally finding mooring, only to have the situation change in the time it takes for Grace to answer the phone.

Maguire is also good in a tricky role. At times he flirts with going too far with Sam's falling apart, too over the top.

Yet who are we to say? How can anyone who has not gone through the torture, who has not had to make the unthinkable choices that Sam has made to get back to his family, know how they would respond? We can't, and it's presumptuous to think differently.

Mention also must be made of Madison and Mulligan, who play the girls.

They're fantastic; their comfort with their characters, their unaffected portrayal, makes what they're going through all the more devastating.

"Brothers" gets at that devastation most effectively, the debilitating effect war can have on a family when one of its members is killed — and even when they're not. Or on this case, both.