Yup, this is the movie about the 17-year-old kid who still sucks his thumb. But don’t get too excited: there isn’t a lot of hot thumbsucking action or anything like that. Instead there’s a lot of adolescent angst, and the fact that it’s so achingly poignant and pointedly hilarious even if you’re way beyond high school makes me suspect that none of us ever really outgrow that teenage insecurity. The thumbsucking is a metaphor, see, a crutch, a security blanket, not the stubborn clinging to childhood that the obvious interpretation would suggest but an expression of fear, that there’s nothing to grow up for, that life is gonna just keep on being more of the same dull routine. Cuz it’s not just high-schooler Justin Cobb (Lou Pucci) who sucks his thumb, though he’s the only one who does it literally: there’s his mom, Audrey (Tilda Swinton: Constantine), whose crutch is her obsession with TV actor Matt Schraam (Benjamin Bratt: The Great Raid); there’s his dad, Mike (Vincent D’Onofrio: Law & Order: Criminal Intent), who’s so insecure about growing older that he insists Justin call him and his wife by their first names, and not “Mom and Dad.” It’s no wonder Justin is a mess, frankly, and yet his parents aren’t bad people, just, you know, scared kids trapped in grownup bodies; even the two other adults around him who want to help — his dentist (Keanu Reeves: Constantine), who worries about what thumbsucking is doing to his teeth, and a teacher (Vince Vaughn: Wedding Crashers), who frets that Justin isn’t “applying himself” — don’t realize that their attempts to straighten Justin out are more about their own needs than Justin’s. Director/screenwriter Mike Mills, working from Walter Kirn’s novel, keeps it all perfectly modulated, balancing wisely observant humor with performances that are wonderfully sneaky in their insight — Pucci makes an auspicious debut in a leading role, but if there’s any justice in movieland, this’ll be the role that finally convinces audiences that Keanu Reeves is a lot slyer and smarter than he’s gotten credit for.