Ghosts (15)

A Nick Broomfield film without Nick Broomfield - drawling voice-over, unsteady boom microphone, stumbling intrusions - is already a novelty, but Ghosts is something else: a hard-hitting docudrama about a migrant Chinese worker who comes to England and ends up on the fateful road toMorecambe Bay, where 23 Chinese cockle-pickers drowned in February 2004.

An impoverished mother (Ai Qin Lin) pays $25,000 to be smuggled into the UK where, she has been promised, she will earn enough to relieve her family's distress back in China. The reality proves somewhat different for her, lodging in a filthy suburban semi with four or five to a bedroom and obliged to slave at repellent and underpaid factory jobs. As a study in exploitation it could hardly be more straightforward, and Broomfield's script (with Jez Lewis) doesn't really add much to what's written all over Ai Qin Lin's eloquently suffering face: show me the way to go home.

Her untutored performance, and the knowledge that she herself suffered much as her character did eight years ago, lend an overwhelming pathos, while the horror leaks out of almost every frame (there's an extraordinary shot of the tide coming in at Morecambe).

Broomfield, inspired by Ken Loach and perhaps too by Michael Winterbottom in his exposure of the migrants' plight, has made a film surprising in its intensity and compassion. I hope he won't mind my saying that I never knew he had it in him.