About once a year—twice, if we’re lucky—a first-time director shows up with something original, electrifying, and humane, a film that shows us a new way to see, that presents complex and memorable people in whom we recognize ourselves. Last year, it was Joshua Marston and Maria Full of Grace. This year, it’s writer and director Mike Mills, and his film is Thumbsucker.

THUMBSUCKER ( * * * * )
Directed by Mike Mills.
Starring Lou Pucci, Tilda Swinton, Vincent D’Onofrio and Vince Vaughn.
(R, 96 mins.) At the Osio Cinemas.

Justin Cobb (the excellent Lou Pucci) is 17. He lives with his parents and younger brother at the edge of the Oregonian suburbs. He goes to school. He’s in the debate club. And he isn’t happy. Justin lacks confidence, unable to make it happen with the girl he likes. His schoolwork isn’t what he knows it should be. And he sucks his thumb.

It’s such a beautiful trope, the thumbsucking, because it works two ways. First, it’s a big deal unto itself, a socially unacceptable act and a relic of childhood, like bed-wetting, that adolescents are supposed to have left behind. It’s also a symbol of something else. Justin is different; he does something that others don’t do and can’t accept. His father (Vincent D’Onofrio), a college football player whose professional dreams were dashed by a knee injury, insists on getting the problem “under control.” His mother (Tilda Swinton) clucks and frets over her son’s habit. And Justin’s new-age orthodontist (Keanu Reeves) attempts to hypnotize him out of it. When Justin can’t suck his thumb, his anxiety runs amok, turning him sweaty and wiggy-eyed, plagued by fear.

What’s wrong with him? Nobody quite knows. On the surface, his life isn’t awful. His dad is a jerk, but mostly a benign one; his mother is loving, if distant and inappropriate at times. School isn’t great, but his debate coach, played with gorgeous restraint by Vince Vaughn, believes in Justin. But Thumbsucker reminds us: No matter what your situation, in whatever time or place, it’s just not easy to be a teenager. The world is complex and often harsh, and teenagers don’t have the experience, or the self-knowledge, to make much sense of it. They search, and they cope however they can. As the orthodontist says, it’s a wonder more people don’t suck their thumbs.

Of course, they do: They smoke and drink and take drugs and have sex and are imprisoned by coping mechanisms and addictions of every stripe. Thumbsucker is fascinated by addiction: Justin’s mother, a nurse, gets herself transferred to a treatment center, where she can learn more about it and support people through it. Better, Thumbsucker understands that people can be, and almost always are, addicted to far subtler things than substances—fantasies, dreams, and ideas of themselves.

Mills has written a gorgeous script, funny and wise and unique, stylized and moody but never tipping over into the realm of the self-consciously quirky. (In many ways, Thumbsucker is what You and Me and Everyone We Know wanted to be.) His direction is artfully nuanced and extremely attentive, resulting in a powerful ensemble piece with an adorable, vulnerable star turn from Pucci. Even the music —the Polyphonic Spree performing lugubrious covers in addition to several originals—is perfect. Wherever Mike Mills has been hiding, his emergence is a cause for celebration.