"Thumbsucker" has such a lovely tone, it's easy enough to forget you've heard this dysfunctional family song many times before.

Justin Cobb (Lou Taylor Pucci) has yet to kiss a girl, stand up for an idea or just plain live for himself. He has a silent crush on classmate Rebecca (Kelli Garner) but hasn't the nerve or emotional constitution to start up a relationship. And he can't seem to keep that thumb out of his mouth. His mother, Audrey (Tilda Swinton), a nurse who indulges in fantasies involving a television star (played by Benjamin Bratt), is sympathetic to Justin, but his father (Vincent D'Onofrio) is becoming increasingly upset about the "problem." One intervention later and Justin's popping prescription medication for ADHD and wiz-kidding his way through debate competitions. He becomes so intensely competitive, however, he spirals again, to the consternation of his family and debate teacher, Mr. Geary (Vince Vaughan).

More interesting than Justin's evolution from oddball to balanced person -- not to mention a harmonic convergence of moral closures for just about everyone else -- is directorand co-writer Mike Mill's guiding hand. "Thumbsucker" is a gently stirring symphony about emotional transition filled with lovely musical passages and softly nuanced performances. Swinton's achingly subtle, D'Onofrio's a bullish prince in the making and Pucci makes youthful awkwardness memorably endearing.

-- Desson Thomson