A triumph of affectionate and even passionate portraiture, this debut feature by cowriters Ryan Fleck and Anna Boden focuses on three complex characters: a politically radical junior high history teacher (Ryan Gosling) who’s devoted to his work but also addicted to crack, a fearless 13-year-old student (Shareeka Epps) who stumbles onto his secret and forms an emotional bond with him, and a smooth local dealer (Anthony Mackie) who employed the student’s brother before he went to jail and now wants to take her under his wing. Their story is unpredictable, beautifully acted, and revelatory in its moral quandaries. Gosling’s character is the most believable protagonist in any American movie I’ve seen this year—an immature mess, but charismatic, multifaceted, and sincere, the sort we can’t really dismiss without dismissing some part of ourselves. Fleck directed. R, 106 min.