The first scene of Short Term 12 both sets the tone and sums up this indie drama from second-time director Destin Cretton. Light banter, outside a foster care facility, is suddenly overshadowed by the darkest of clouds, as one of their number bursts from the door in a desperate bid to escape. It’s a shocking scene for all its fireball intensity, proof that in this business hair-trigger responses are an everyday occurrence.

Leading the film is Brie Larson (who can also be seen in Joseph Gordon-Levitt’s Don Jon this month). She plays Grace, one of the care workers who has enough of a troubled past to suggest she’s been papering over the cracks. When pensive new girl Jayden (Kaitlyn Dever) arrives at the facility, her presence forces Grace to consider her own deep well of sadness. It leads them both onto a brighter path, with tears and tenderness, but never to the point of mawkishness.

Cut from the same cloth as Ryan Fleck’s Half Nelson, the 2006 film that announced Ryan Gosling, Short Term 12 boasts a similar integrity in its bones. Cretton, who based the script not only on his 2008 short of the same name but also on his own experiences working in this world, draws some impressive naturalistic performances from his support cast, who bubble away in the background.

Front and centre, Larson, who won Best Actress at the Locarno Film Festival for the role, gives a career-making heart-on-her-sleeve turn as Grace, who – like so many of her colleagues – is just a few years older than those they look after. It’s a jagged film at times, not always fully fleshed out, as it strays dangerously towards melodrama. But as a stepping stone for both Larson and Cretton, it leaves you tantalised as to what they’ll do next.

General release from Fri 1 Nov.

Short Term 12 - official UK Trailer