Nicole Kassell's “The Woodsman” tightly shackles the viewer to a man most people would prefer not to meet in real life: a convicted child molester, paroled and walking the streets.

As a hook — or gimmick, depending on how you look at it — first-time director Kassell also endows Walter (Kevin Bacon) with a host of sympathetic qualities. He's modest and hardworking. He loves his family and craves a relationship with them. He's racked with guilt and seems determined to quell his predatory sexual urges. He is, to put a fine point on it, bothersomely human.

If “The Woodsman” is guilty of a certain glib humanism, it at least acquits itself of mediocrity, extending fascinating endoscopic insight into the mind of an addict. Bacon is scary good as a man in psychological stalemate, and Kassell — who won a Sundance screenplay award for the film along with co-writer Steven Fechter — stocks the storyline with an arsenal of narrative gadgets that allow the actor to fully apply his skills. It's wrenching, for example, when Walter confesses his past to his brackish new girlfriend — played by Bacon's real-life wife, Kyra Sedgwick — and, not receiving the rebuke he expects, rejects her as a sicko. Self-loathing is rarely expressed so seriously or plausibly.

Perhaps a little too forcibly, Kassell weaves a fairy-tale theme into “The Woodsman.” When a girl in a hooded red coat comes along, we don't know if Walter (who works in a lumberyard) is the big, bad wolf or the girl's wood- chopping savior. Often, it seems as if Walter himself is the child lost in the wilderness, abandoned by his family and antagonized by a suspicious cop (Emmy-winner Mos Def). Thinking- woman's hunk Benjamin Bratt is an intriguing question mark as Walter's brother-in-law, Carlos, the felon's only link to his family and, conversely, a barrier between them.

Kassell is enough of a realist not to make any promises about Walter; like Travis Bickle of “Taxi Driver” or Billy Bob Thornton's racist prison guard in “Monster's Ball,” he's a man in search of himself, and the outcome remains vague, as it must. Still, Walter ultimately gives us cause for optimism — and whether that constitutes responsible drama or deluded liberal fiction is for the viewer to decide.