Grace (Brie Larson) and Mason (John Gallagher Jr) are particularly dedicated workers at a care home for troubled teenagers. Then there are the kids themselves. About to turn 18, Marcus (Keith Stanfield) is the kid with the aggressive front and the inner fragilities. Sammy (Alex Calloway) is the introverted boy who runs manically through the garden when he is particularly troubled. He remains an enigma throughout. The two young actors’ performances are utterly convincing.

There is more than a touch of cinema verité about Short Term 12, and also something that goes beyond gritty realism. It’s that elusive quality in a film that opens your eyes in a fresh way to harsh realities, in this case, to what happens when kids are abused or neglected.

Some of the teenagers are on prescription drugs, one is stashing weed in the mattress. No surprise to learn that director Destin Cretton based his film on his experiences working at a facility similar to the one depicted here.

As the story progresses, Grace the care worker takes a particular interest in a petulant young girl called Jayden (Kaitlyn Dever) who announces on arrival that she will not be making friendships because they will be temporary. Nothing personal, she says, but she will shortly be going back to live with her father.

However, Grace has suspicions about happenings at home, which she is determined to deal with, despite clashing with her supervisor.

Short Term 12 is strikingly imaginative in how it presents the children and their problems at the care home, where it isn't all doom and gloom, incidentally. Sadly, the film becomes mawkish and, well, soppy in a parallel story of love between two characters.

There is, too, a serious creative fault line in the action between the clear-eyed depiction of life at the care home and the director’s urge to hit a dramatic climax. Short Term 12 overreaches itself with a surfeit of sensationalism towards the close, thereby spoiling a film that could have been so much better. Short Term 12 is released at the IFI and selected cinemas.

Paddy Kehoe