In this decade, more than 5,000 Americans have been killed in combat zones, and the families of most of those warriors have learned the dreaded news from a messenger like Capt. Tony Stone (Woody Harrelson).

"There's no such thing as a satisfied customer," Stone quips to his new partner, Staff Sgt. Will Montgomery (Ben Foster). Montgomery was wounded in Iraq and reluctantly accepted a stateside assignment to the Army's casualty notification service.

But riding shotgun with Stone is another kind of combat. The captain is a stickler for the rules of informing kin about casualties: no deviations from the scripted expression of regret, including hugs or other physical contact.

But Montgomery wavers when a grieving father (Steve Buscemi) spits in his face, and he succumbs to outstretched affection when a young widow (Samantha Morton) thanks him for the hard job he is doing. When he returns the next day to a house filled with flags and donated casseroles, the insufficiency of good intentions is painfully clear.

"The Messenger" is the debut film of writer and director Oren Moverman, but it's worldly wise, with two well-rounded characters. In Stone, the never-better Harrelson has an unusually juicy role to chew on, a military lifer and recovering alcoholic who waits until the coast is clear to unleash his gonzo wisecracks. He has a volatile chemistry with Montgomery, whose mental anguish and physical pain are kept corked until a predictable meltdown involving his ex-girlfriend's wedding.

This muscular performance should open doors for Foster, who's been relegated to playing psychotic weasels in movies such as "3:10 to Yuma" and "The Punisher."

Like "The Hurt Locker," this film doesn't take political sides — and it's all the more heartbreaking because of its restraint. The only message in "The Messenger" is that wars come home with the soldiers, both living and dead.