The undercurrents of adolescent cruelty churn queasily in Charlie Polinger's stylish first feature, ''The Plague.''
The title of Polinger's film might bring to mind Stephen King or recent global history, but ''The Plague'' is set entirely around the clear, chlorinated pools and shadowy hallways of a water polo camp, circa 2003. There, 12-year-old Ben (Everett Blunck), a scrawny and sensitive kid, arrives for the second session. That's a key detail: Is there any greater horror than joining a summer camp where the friend groups are already established?
But there is really only one group: a lewd and boisterous lot led by a smirking, cocksure kid named Jake (Kayo Martin). And there is one outcast: Eli (Kenny Rasmussen), the kind of 12-year-old who's obviously smart but whose awkward, introverted manner and fondness for things such as magic tricks and ''Les Miserables'' inevitably make him an outsider. He also is covered in acne and has rashes across his back. Jake and the rest all say he has the plague. ''No cure for him,'' Jake tells Ben.
These are the troubled coming-of-age waters that ''The Plague'' swims in. From the start, it's clear that Polinger, who also wrote the film, has a keen eye for both darkly gleaming surfaces and for the roiling torments that lurk below. ''The Plague'' is by no means charting new ground when it comes to adolescent torments; this is a movie working with very recognizable preteen types. But Polinger's talent for crafting ominous, murky atmospheres and perceptive adolescent dynamics make ''The Plague'' an auspicious debut feature.
While coming-of-age tales have played out before on baseball diamonds and football gridirons, the deep pools of water polo are a more novel setting. From the start, Polinger's camera, working with cinematographer Steven Breckon in 35 mm, drifts eerily toward the quiet frenzy underwater: the kicking legs and agitated bubbles. Their entry to adulthood is a sink-or-swim, with nothing to stand on.
When their coach (Joel Edgerton, also a producer) asks what water polo is, he calls on Ben, who offers: ''Working together as one big family, or whatever.'' But far from collective, the world of ''The Plague'' is primal and survivalist. The coach is kind but ineffectual. Parents are distant and out of reach. This is ''Lord of the Flies'' in the pool.
That connection is most clear one night when the boys sneak out to some abandoned building, make a bonfire, smash a bunch of stuff and watch as Eli — who usually isn't even allowed in their presence — dances by spinning wildly around. Ben is more sensitive than Jake and his pals, and he looks concerned for Eli as soon as he arrives. But he's also more anxious about his own, tenuous-at-best place in the group, and he uses this moment to crash into Eli, knock him down and then make a show of cleaning off any ''plague'' residue on his arm.
In ''The Plague,'' ostracism is as permanent and irremediable as any pandemic infection. As big-screen bullies go, Jake is a classic one, terrifically played with smarmy malice by Martin. Jake isn't taller or stronger than the rest, but he has a maturely manipulative feel for weak points. He doesn't so much unleash putdowns as he repeats back an awkward answer and lets his victim twist in the wind. Psychologically, he towers over the rest.