Low-key yet brutal, Half Nelson is exactly the kind of movie Hollywood will never make. Notably, it's entirely clich© free. There's no deliverance for Dan Dunne (Ryan Gosling), an eighth-grade teacher whose raging crack habit is steadily taking over his life. There's no real turnaround for 13-year-old Drey (Shareeka Epps), one of Dan's students who's being eyeballed for drug-delivery service by the neighborhood dealer, Frank (Anthony Mackie). And though Dan and Drey forge an alliance amid their unstable worlds — they kinda have to after Drey discovers Dan, who's also her basketball coach, hitting the pipe after a game — the friendship is a shaky one. "I want to know consequences," Dan tells his class, trying to get them excited about his latest history lesson (later, he'll engage in an arm-wrestling contest to illustrate "turning points"). But in his own life, Dan can barely face another day without getting high first.

The first feature from producer-writer Anna Boden and director-writer Ryan Fleck, the unflashy Half Nelson uses subtlety to speak volumes. Its beats are succinct but intense: when Dan's ex-junkie ex-girlfriend briefly appears, she's rosy cheeked and sporting an engagement ring — pretty much the embodiment of the kind of hope for the future that Dan can't imagine ever having.

The film doesn't spend much time on exposition. We never learn how or why Dan started using. Like last year's Down to the Bone, Half Nelson burrows into the mind of a full-blown addict whose ability to fake normalcy becomes more precarious by the day. The first time the stern principal hooks Dan into an emergency meeting, it's to reprimand him for straying from the lesson plan. The second time, he's just taught a class on hyperdrive, with an oozing nosebleed to boot, and his double life is in full crumble.

Even as she comes to terms with her favorite teacher's shortcomings, Drey has plenty of her own problems. Her weary mother barely has time for her between double shifts; her father is merely a voice on the telephone; and her older brother is incarcerated, a circumstance that's the direct result of his association with Frank. To Dan's dismay, the candy-chomping Frank insinuates himself into Drey's largely unsupervised life, and an odd tug-of-war results. Clearly, neither man is a good father figure, not by any stretch. There's a tense confrontation between Frank and Dan that perfectly illustrates Half Nelson's ability to inject unpredictability into familiar movie moments. The scene also picks up a key thematic thread — can one man make a difference? — that's echoed by Dan throughout the film, particularly in a late scene involving a visit to his grossly liberal (and liberally inebriated) parents.

Half Nelson is a film with no wasted space, and that goes double for its acting. Epps (stoic) and Mackie (charmingly manipulative) are excellent, but this is Gosling's game from the start. His layered, sympathetic performance conveys not just Dan's jittery freak-outs and frustrations but also his deep inner anguish. It's what makes watching Half Nelson a wholly satisfying experience. (Cheryl Eddy)

HALF NELSON

Opens Fri/25

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www.halfnelsonthefilm.com