Gone Baby Gone

For his first time behind the camera as a director, the actor Ben Affleck has chosen a brooding, serious drama about missing children, wayward parents and idealism lost and regained. “Gone Baby Gone” is based on the novel by Dennis Lehane, who wrote the similarly themed “Mystic River,” which Clint Eastwood turned into a modern classic. If Mr. Affleck hasn’t raised his material to that rarefied level, he has taken a satisfyingly tough look into conscience, to those dark places where some men also go astray.

The story wants to break hearts: 4-year-old Amanda McCready, a blond doll, has disappeared without a trace amid the squalor of her South Boston neighborhood. The cops are out in formation, as are the television news vans, antennas raised high and all but trembling for blood. Staring into the cameras, the neighbors eagerly offer ready-made headlines and self-flattering condolences: they’re coming together, everyone loves Amanda. The days tick past and the child’s anxious aunt, Bea (Amy Madigan), seeks help from a local private investigator, Patrick Kenzie, a squirt who looks as if he just dropped out of college and is played without an ounce of actorly ingratiation by Casey Affleck, the director’s younger brother.

I’m not sure exactly when Casey Affleck became such a good actor. Steven Soderbergh tapped him a few years back for recurring third-banana duties in the “Ocean’s Eleven” films, and Gus Van Sant put him in “Gerry,” his 2002 avant-garde feature, in which Mr. Affleck roamed around a merciless desert landscape with Matt Damon, with whom he took turns playing Beavis and Butt-head, Vladimir and Estragon.

More recently he stole the show from Brad Pitt in the western “The Assassination of Jesse James by the Coward Robert Ford.” One of the unusual things about his performance as Ford was its lack of sentimentality. He didn’t plead the character’s case or remind us of his own humanity; he just played the role.Most actors want you to love them, but Casey Affleck doesn’t seem to know that, or maybe he doesn’t care. Patrick doesn’t cuddle or kiss up. He takes the job Bea offers despite the reluctance of his live-in girlfriend and partner, Angie (a solid Michelle Monaghan), but he doesn’t look like anyone’s idea of a savior. With his sneakers and jeans and small-man’s swagger, he comes off like one of those toughs who never leave the neighborhood and would sooner swing a bat at your head than at a ball.Mr. Affleck is already deep into the character right from the start, but neither he nor his director let on all they know about Patrick. There’s something about this guy that needles, that helps keep an already tense story on edge.

Despite its terrible question marks — who stole Amanda and why, is she alive and for how long — “Gone Baby Gone” pays closer heed to the enigmas of soul and heart than to clues and guesswork. There are false leads, dead ends, brandished guns and nightmarish discoveries, as well as shadows and controlled camerawork, but mostly there are human frailties and thrown-away, forgotten lives. The screenplay by Ben Affleck and Aaron Stockard whittles down but doesn’t reduce Mr. Lehane’s material, pulling out details and types that stick to the screen, including Amanda’s mother, Helene, played by a ferocious Amy Ryan. Talk about not wanting our love! Ugly in voice and deed, Helene is the underclass mother from hell, a hazard, a druggie, a villain in waiting.Helene is a nightmare, or at least the embodiment of a certain familiar fear: the bad woman (welfare queen) periodically held up as a symptom of some grave social disorder. Working with her supportive, encouraging director, Ms. Ryan plays with this stereotype and our sympathies to the breaking point. Deploying her broad Boston accent like a weapon, she whines and retreats, testing Patrick’s sympathy with each one of her pathetic excuses. It’s a gutsy, sensational performance that adds layers to an already spiky, provocative creation. At first you hate the woman and love the actress, though because Ms. Ryan and Ben Affleck are wise to the ways of scapegoating, you learn why that hate is misplaced.It isn’t all that surprising that Mr. Affleck is so good with his performers, or at least most of them. The film has been wonderfully populated with character actors like Titus Welliver, who plays Lionel, Helene’s straight-talking brother, and Michael K. Williams, one of the outstanding villains from the HBO drama “The Wire,” who shows up here as a friendly cop.

Just as memorable are two unfamiliar faces: the newcomer Jill Quigg, who has a few startling scenes as Helene’s comically, scarily belligerent friend Dottie; and the Boston rapper Slaine, whose cool, dead-eye performance as the drug dealer who leads Patrick right into the heart of darkness adds menace to one of the film’s strongest, most harrowing scenes.

Mr. Affleck trips up now and again, mostly with his older, famous peers Ed Harris and Morgan Freeman, who delivers one of the more unpersuasive performances of his career as the head of the police department’s missing-children division. The director does better with Mr. Harris, who plays a hotheaded detective in a distracting hairpiece, though again Mr. Affleck doesn’t control the performance as well as he does those of the other cast members. He also wavers when he lingers too long over the crumpled faces and bodies of what appear to be real South Boston natives.

Even so, one of the graces of “Gone Baby Gone” is its sensitivity to real struggle, to the lived-in spaces and worn-out consciences that can come when despair turns into nihilism. Mr. Affleck doesn’t live in these derelict realms, but, for the most part, he earns the right to visit.