Camille (Hugon) has just turned nine when he starts acting strangely. At first his parents think that he's become obsessed with the new video camera that his Uncle Serge (Berling) has bought him. Then, while his father's away, he tells his mother (Huppert) that he wants to "go home" to his real family.

Terrified that her son is about to have some sort of breakdown, his mother lets him lead her to a strange address in Paris. There they meet Isabelle (Balibar) who tells the distraught mother that Camille is the reincarnation of her own dead son and that from now on she'll be looking after him.

Fraught with understated family anxieties, sexual tensions, and psychological shenanigans, "Comedie de L'Innocence" is part ghost story, part psychiatric case study. As Ruiz himself has commented, it's a film that "involves fantasies rather than phantoms".

Building on the creepy atmospherics of the horror genre, Ruiz crafts a deeply disturbing tale of Oedipal crisis in which Camille's confusion about his two mothers is only half the story. As we realise, the adults are just as conflicted as the child.

In their roles as the boy's mothers, Huppert and Balibar are superb. Both manage to suggest the profound mental instability of their characters in very different ways - Huppert's nervous exhaustion, Balibar's manic smile and its hints of potential psychosis.

In the end, though, it's Ruiz's directorial ability that makes this film truly spooky. Keeping us off-balance, Ruiz refuses to reveal everything to the audience, asking instead that we try and fit together the pieces of this fractured jigsaw puzzle. It's this mysteriousness that makes "Comedie de L'Innocence" one of the most intelligent and disturbing films of the year.

In French with English subtitles.

"Comedie de L'Innocence" is in UK cinemas on Friday 8th March 2002.