Beautiful West Cork is photographed like a crime scene, chilly and sinister, in this atmospheric family drama about grief and guilt, and the life-changing burden of causing a terrible tragedy. In his first acting role Ollie West is superb as Kevin, a sensitive, moody teenager with chipped black nail varnish. Kevin is constantly in trouble; he’s nothing like his army veteran dad (David O’Hara), or popular big brother Robbie (Éanna Hardwicke), whose easy smile wins him the girl they both like. Kevin feels like an outsider in his family; partly the problem is that he reminds everyone of his mum, an artist who died in circumstances that make her unmentionable in their house.

The family is already bewildered by grief. Then, at around the 30-minute mark, something happens: Kevin inadvertently causes a tragedy so awful that you wonder how it’s possible to carry on. Being a teenager, with a still-developing frontal lobe, impulsive and lacking judgment, he doesn’t own up to what’s happened, and an avalanche of consequences pile up.

The acting is all round superb. West is a real find as Kevin, charismatic and intense; David O’Hara is terrific as his dad, clenched and unable to hide how disappointed he is by his son, but with traces of emotional depth underneath; he’s not the predictable stereotype of a ramrod disciplinarian ex-soldier. Still, a little bit of cliche does creep in, especially in the scenes in which Kevin takes care of a tiny sparrow he finds injured, trying desperately to keep it alive; it feels a bit gimmicky for such a sombre film. In fact, the drama here is cooled to such a low temperature that in the end it’s perhaps a little too chilly to be fully heartbreaking.

• The Sparrow is in Irish and Northern Irish cinemas from 5 July.