"Sleepwalking" is well-acted but convoluted, a small-scale family drama that walks the walk, but doesn't seem to know half the time where it's going. In a bid for indie cred, first-time director William Maher and screenwriter Zac Stanford (2005's "The Chumscrubber") root their characters in a haze of unhappiness and bad luck; these folks can't seem to catch a break, and tend to screw up most of the good things they've got going. Accompanying them is a ruminative music score and a lot of scenes of them driving around or standing around or sitting around waiting for something to happen.

When her no-good boyfriend is busted for growing marijuana on their property, single mother Joleen Reedy (Charlize Theron) moves herself and 11-year-old daughter Tara (AnnaSophia Robb) in with younger brother James (Nick Stahl). Terrified that she might be screwing up her child's life, Joleen up and walks out without notice, leaving James to take care of her. A disastrous visit from a social worker and an unfortunate job firing later, Tara has been whisked off to a foster care center and James is left unemployed and homeless. With nothing left for them there, James and Tara take to the open road. When their money runs out, they opt to stay with his estranged, gruff, set-in-his-ways father (Dennis Hopper), a farmer who promptly settles back into his old habits. Suddenly, it is very clear what all of James' and Joleen's problems as adults stem from.

"Sleepwalking," a title with an underlying meaning that doesn't reveal itself until the end, is most effective in the second half, when the wounds of James' and Joleen's childhood rear their ugly heads with the entrance of their father, a sad, pathetic monster of a man who doesn't exactly have the best parenting skills. With James finding himself resorting back to his younger days and allowing his pop to maliciously control his every move, he is helpless, at least at first, to stop the same thing from happening to Tara. Dennis Hopper (2005's "Land of the Dead") is so believable he's scary as Mr. Reedy Sr., unflinchingly disappearing behind the eyes of a man who is without remorse in making other people's lives a living hell.

The other performances are quite good, too, though the film makes a notable error in making James the person whose point-of-view we follow. Nick Stahl (2005's "Sin City") does fine, understated work in the role, but it is the lovely AnnaSophia Robb (2007's "Bridge to Terabithia"), as Tara, who the viewer cares most about and whose story is the most poignant. Tara is a good kid saddled with a mother who abandons her and an uncle who cares for her, but has too many troubles of his own to be an ideal surrogate parent, and the viewer is led to only hope that she'll be able to turn out all right in the end. And finally, as the white trash Joleen, Charlize Theron (2007's "In the Valley of Elah") continues to dirty herself up so that she can be taken seriously. Theron is such a strong, astute actress, though, that her looks should no longer be an issue. She's more than proven herself by now, and the supporting part of Joleen is a bit beneath her.

Director William Maher rustles up a conclusion to "Sleepwalking" that is intended to be bittersweet yet positive, but it's not to be bought for a second. Yes, Joleen comes to the realization that she has made a lot of mistakes and wants to make up for them, but can her unsavory actions really be swept away and forgotten about? And, for that matter, is she really the best person to be raising Tara? Moreover, should the courts even let her? Considering all the evidence presented, the answer to these questions is no, but Maher pushes a yes on the matter, refusing to deal with the reality of the touchy situation. "Sleepwalking" keeps one's attention, and a few lighter, quirkier moments, such as one involving a roller-skating Tara at an indoor pool, help to temporarily brighten the proceedings. The ultimate path that the narrative takes, however, is on rockier, less sure ground, and it never recovers enough for the film to be more than a valiant failure.