The key to any film noir worth the name is the casting of a deliciously amoral femme fatale as a catalyst for double dealing and death.

Typically, Pedro Almodovar fills the femme's stilettos with a blackmailing transvestite, greedy for the cash to complete her sex change.

When we first meet Zahara she is Ignacio (Ignacio Perez)), a choirboy at the Catholic school where he is the object of lust (and love) for Principal Father Manolo.

Terrified by the unwanted attention, Ignacio strikes up a friendship with fellow pupil Enrique, only for a jealous Manolo to engineer the boy's expulsion.

Vowing revenge, Ignacio approaches Enrique (Martinez) years later, after the latter has established himself as a leading young film director. (Remind you of anyone?)

He presents him with a script - The Visit - which describes the sexual abuse perpetrated by Father Manolo all those years ago.

Intrigued, Enrique gets to work...only to find that the story of how the sweet-natured Ignacio became a heroin-sated transvestite asks more questions than it answers.

After the over-complicated Talk To Her, the Spanish director is back on form with this deft film noir, which still resolutely remains an Almodovar movie.

No-one is quite who they seem and the director fiendishly leads the audience - helped by a barrel of red herrings - to a pay-off that is as structurally rigorous as it is emotionally satisfying.

Bernal - who first attracted attention in Y Tu Mama Tambien - stamps his authority over the ambiguous character of Ignacio, whilst Martinez - loosely modelled on the young Almodovar - impresses as the sober pillar of calm amidst all the duplicity and lies.

Almodovar insists that this isn't a settling of scores, after his own fate at the hands of his Catholic teachers, but he can't resist one barbed line at their expense.

After perpetrating a mortal sin, one priest comments to another that God is their only witness. "Ah, but he's on our side," comes the reply.

Tim Evans