Joleen Reedy (Charlize Theron) is the kind of broad who has second thoughts right before nailing her date on the kitchen table while her brother James (Nick Stahl) pretend-sleeps on the couch—instead, she removes her daughter Tara (AnnaSophia Robb) from the only bedroom and continues the festivities there. Sleepwalking, the directorial debut of William Maher, is the kind of film that expects you to respond to this scenario with a sort of grim, Pavlovian determination, knuckling down for 90 minutes more of the same in the hope of some reward. Nearly relentless in its bleakness, Sleepwalking follows Tara and James as they strike out of their dead-end town when deadbeat Joleen buggers off. They wind up at their American Gothic homestead, subject to the relentless assholery of the family patriarch (Dennis Hopper), which is what drove James and Joleen away (and possibly crazy) in the first place. Stahl seems as adrift as we are within James’s utter blankness, and Robb—a naturally mesmerizing presence—hints at a better movie when feeling her oats in sunglasses and roller skates while two star-struck young boys look on. Theron and Woody Harrelson (as James’s party pal Randall) provide vitality against the film’s heavy load, but they aren’t around long enough to keep it from collapsing under its own portentous weight.