“I never dreamed the lives of my grand- children would come to see so much violence and bloodshed…”

So says the opening voice-over but, through its first half hour, the film is rather quiet. When we meet Chris (Jamie Bell), he’s sitting under a tree with a pretty girl, in one of these perfect little moments of happiness that feel like they could last forever. It’s a perfect little moment of cinema as well, with almost-Technicolor cinematography by Tim Orr and atmospheric music by Philip Glass. David Gordon Green’s artistic sensibilities seem of another era, like the 1970s of his mentor (and “Undertow” producer) Terrence Malick; even the titles are retro, with the stylish yellow font and the copyright number.

Things get a little rocky when the pretty girl’s father chases after Chris, who’s apparently always getting into trouble and getting picked up by the cops, but the mood eases again once the boy’s back home with his father John (Dermot Mulroney) and his little brother Tim (Devon Alan). We learn that when their mom died, the old man took the kids out of school and moved out here in the sticks. They seem to live in their own little world, with John often driving out to town in his beat-up car, leaving Chris to work around the house and Tim to read books and eat paint. Yeah, paint.

After this slow but intriguing set-up, “violence and bloodshed” comes along in the form of Deel (Josh Lucas), John’s brother, who just got out of jail. While they initially seem to get along all right, it soon becomes clear that there’s bad blood between them. Something about the boys’ mother, how their grandfather was “one hell of a pirate” and cursed Mexican gold coins! I won’t go into details, but “Undertow” turns almost into a horror movie for a reel, after which the brothers are forced to run away.

Their journey takes them into the woods, though little towns and ultimately to an idyllic community of squatters. All of these little sequences are interesting on their own, driven by the gorgeous cinematography, great Glass score and convincing young actors, but they don’t really add up. Whereas the impressionism of “George Washington” worked itself into something of a super-hero origin story and All the Real Girls remained focused on a very moving love story, “Undertow” is kind of all over the place. It touches upon age-old themes of brotherhood, greed and good versus evil, but what Green wants to say about this remains obscure. I still think he’s an exceptional filmmaker, but this won’t be one of his most memorable pictures.