One mark of a world-class actor is the ability to convince us that a character exists outside the confines of the screenplay. It is one thing to skillfully deliver a dramatic monologue, to tap depths of volcanic rage or crippling grief for a big Oscar moment played to the cheap seats. Far rarer and more valuable are performances that quietly suggest what isn't spelled out: key character details expressed through gait or inflection; off-screen experiences hinted at with a look, a gesture, or a wayward smile. This is really a difference between an actor and a performer. Tom Cruise is a great performer. Philip Seymour Hoffman is a great actor. So is, for example, Patricia Clarkson.

In The Messenger, Ben Foster plays Staff Sergeant Will Montgomery, who is shipped home after an injury, and assigned to serve out the last three months of his enlistment on "notification duty" with the apparently unbalanced Captain Tony Stone (Woody Harrelson). The two of them are tasked with telling the next of kin that a soldier won't be coming home, a job that consists of knocking on a door, reading from a script ("the Secretary of the Army extends his deepest condolences..."), and bracing oneself for a likely onslaught of abuse.

Eventually, Will gets involved with one of the widows, a sad, lovely young woman played by Samantha Morton. But the plot is the weakest link in a movie that rests largely on Foster's astonishing lead turn, a quiet masterpiece of repressed anger and overwhelming sadness. Until this year, it had seemed like Foster had taken to solely playing psychopaths -- the vicious, beady-eyed villains of Alpha Dog, 3:10 to Yuma, etc. But it turns out that Foster can expand his range by adding layers to the coiled intensity that those roles demanded. For much of The Messenger, we don't know exactly what happened to Will -- neither to lead him to the army, nor to get him sent home. But the fleeting hints of pain and frustration that play across Foster's face in key scenes are more revealing than any amount of exposition.

Watch him tell his ex-girlfriend (Jena Malone), who has come to welcome him home and also to tell him that she's gotten engaged in his absence, that "you don't have to worry about me": with that one line, Foster somehow makes perfectly clear that Will's brave face is a crumbling façade. Or watch him as he is spit on and cursed by a grieving father (Steve Buscemi): Will mostly just stands there and takes it, but Foster manages to convey a maelstrom of emotion that itself tells a story. And on the rare occasions that Will smiles, we get a brief but fully realized glimpse of the kind of person that he used to be.

Foster is so good at filling in the blanks of his character, that when the "real" details begin to come out -- how Will came to be an army mechanic, how his mother "notified" him as a child, the Iraq memory that haunts him -- the movie deflates a little. What the performance suggests and we imagine is richer than what the screenplay later tells us. If that doesn't deserve an Oscar, I don't know what does.

Soldiers on notification duty make an appearance in Jim Sheridan's Brothers, too, to tell Grace Cahill (Natalie Portman) that her husband Sam (Tobey Maguire) has been killed in a helicopter crash in Afghanistan. If you've seen the trailer, you know that Sam is eventually found and returned home, by which point Grace has bonded with Sam's screw-up brother Tommy (Jake Gyllenhaal). Sam's frightening transformation upon his return is the point of the film, and Maguire is terrific in the role. But it is Gyllenhaal, playing a volatile, deeply troubled ex-con, who has the harder job here. In Maguire's case, we see in graphic detail Sam's harrowing experience as a prisoner in Afghanistan, and our minds do a lot of the work of giving what follows its impact. On the other hand, the movie only hints at Tommy's past, and Gyllenhaal is left to do the heavy lifting.

He pulls it off beautifully. Consider the dinner scene early in the film, and Tommy's face-off with his father (Sam Shepard), intent on goading and belittling him; there's so much unspoken family history packed into Tommy's increasingly unsuccessful attempts to contain his anger while his dad throws insults. And consider the suggestion, subtly planted, that Tommy is using his brother's apparent death -- and the resulting opportunity to be a "good guy" -- as a self-esteem boost to make up for decades of playing second fiddle to his star athlete, war hero brother. It's a fantastic, troubling performance -- smaller and quieter than Maguire's, to be sure, but more impressive for it.

Both of these dudes are likely to end up out of serious awards contention, if they aren't already. But I'll take their intricate, difficult work over the technically proficient impersonations (Meryl Streep, Morgan Freeman) and hysteria-fests (Mo'Nique, Helen Mirren) that tend to grab all the attention. Performances like this are what makes a "character actor."