Cracks is set in a remote all-girl boarding school in the 1930s. One of the teachers, the chic and bohemian Eva Green is Miss Jean Brodie except with designer clothes, and more of a tendency to take them off in the open air. She's idolised by a clique of pupils led by Juno Temple and Imogen Poots (the actresses' names, not the characters', believe it or not) until the power balance is upset by the arrival of an aristocratic Spanish girl, Maria Valverde.
That said, the power balance isn't upset very much. There's a flurry of violence at the end, but beforehand the term drifts along with more emphasis on the lighting than on the characters' changing relationships. Jordan Scott's debut film is essentially a picturesque, slow-motion montage of boarding school pastimes: diving practice, a midnight feast, parcels from home, low-level bitching. I kept hoping Dumbledore would pop in and liven things up.