Unfortunately, its superb performances and assured camerawork are overwhelmed by dubious psychology and a clichéd climax.

Like the Peeping Tom-paranoia of similar recent films Disturbia and Civic Duty, this finely crafted debut feature by Scottish writer/director Andrea Arnold packs a wallop.

Though it's paced as a thriller, the film ultimately emerges as a haunting exploration of how grief can weigh on us, and the depths to which it can drive us.

...an erratic yet mostly rewarding debut...