Imagine if in Jaws, the resident of Amity Island who took the appearance of a great white shark most seriously wasn’t the town sheriff but a hormonal 14-year-old girl. The resulting film might be something like writer/director Lucía Garibaldi’s feature debut, The Sharks, which scooped the Directing Award in World Cinema at this year’s Sundance Film Festival.

Amateur performer Romina Bentancur is quietly assured in her role as the movie’s awkward anti-heroine, 14-year-old Rosina, whom we first encounter fleeing her angry father (Fabian Arenillas) after almost blinding her older sister (Antonella Aquistapache) in a bout of malicious horseplay. Rosina runs down the beach that outlines her small village on Uruguay’s coast and seeks refuge in the surf, only to retreat onto land when she spots a large dorsal fin in the waters.

Rosina finds herself a girl who cried “Shark!” as her father dismisses her claims as more teenage petulance. To knock some sense into his troublesome daughter, he ropes Rosina into his gardening crew, where she falls for co-worker Joselo (Federico Morosini), the sort of dopey older boy young girls are so often naively drawn to. Joselo invites Rosina to the garage home he shares with his work buddies, but Rosina’s hopes for a romantic encounter are dashed when Joselo simply pleases himself beside her. Refusing to join in, Rosina is dismissed by Joselo, who ignores her at work.

The sociopathic side of Rosina that left her sister wearing an eye-patch returns as she embarks on a mission with the intent of either harming Joselo or winning his affections. Like the unstable female protagonists of Straight on Till Morning and Ingrid Goes West, Rosina steals the object of her desire’s dog, keeping the mutt in a forest while Joselo scours the town for his prized pooch.

Meanwhile, sea lion carcasses have washed up on shore, indicating that maybe Rosina did see a shark after all. The idea is quickly put to bed by the town’s authorities, who invite a news crew to dismiss any notions of an impending shark attack. But Rosina is determined to lure in both the shark and Joselo.

On the surface, the idea of blood in the water is a pretty blunt allegory for Rosina’s sexual awakening, but Garibaldi never hammers home the metaphor. Rather her film is as restrained as cinema gets, as sleepy and subdued as its seaside setting. There are no great dramatic moments here, simply a collection of minor incidents that build to Rosina’s ultimate act of potentially violent narcissism. In many ways it’s a South American companion piece to Megan Griffiths’ underseen North American indie Sadie, in which a teenage girl similarly plots a disturbing act while ignored by all those around her.

But The Sharks has its moments of humor too, often arising from the idea that Rosina is clearly functioning on an intellectual level unmatched by her family and friends. A scene in which she tries not to lose her rag while helping her luddite mother use a computer is one that will likely resonate with many a teen. Rosina’s expression as she’s forced to listen to a group of her fellow schoolgirls’ filthy discussions of their sex lives suggests she’d gladly detonate a suicide vest in their vacuous presence.

As Rosina, Bentancur perfectly embodies the frustration of that time of life when you’re told to behave like neither a child nor an adult, the purgatory of post-pubescence. Her stiff and gangly presence is like a coil waiting to spring, a scream suppressed. When she cracks a grin in the presence of nobody but herself it’s a moment that’s both unsettling and liberating.

"The Sharks"  3 1/2 stars out of 5

Directed by: Lucía Garibaldi; Starring: Romina Bentancur, Federico Morosini, Fabián Arenillas, Antonella Aquistapache, Valeria Lois