A somewhat schematic script - you can almost see the boxes being ticked as each issue is dealt with - does not ultimately detract from a fine achievement. The story surrounds the succumbing to HIV-AIDS by a life-loving young man at the time when the world was taken by surprise by the ferocity of the hitherto-unknown virus. The various reactions - bewilderment, fear, panic, hatred, self-loathing, guilt, determination, courage, loss, grief and, of course, love - are all charted in the five central characters.

There can be little argument, I'd have thought, concerning the excellence of Michel Blanc's performance; nor of the puzzling awfulness of Lorenzo Balducci's - whyever was this Italian actor cast as an American who had been brought up in Australia?

Julie Depardieu's character is the least developed of the central quintet but nevertheless the actress manages, as ever, to make a fully-rounded contribution.

Emanuelle Beart's striking features and dynamic screen presence make it difficult to assess her as an actress. In the end she didn't convince me she was any kind of writer, but she was entirely convincing as a mother with ambivalence to her baby. The scene where her character talks to her own mother (the late Maia Simon, in a brief but noteworthy final performance) about the difficulties surrounding her own birth is one of the most tender in the film.

Johan Libéreau is touching as the doomed Manu, fleshing out what seems to me to be a somewhat idealised character - unreflective but sensitive, foolhardy yet vulnerable.

But the film ultimately belongs to Sami Bouajila as the policeman who finds himself in the most unexpected of relationships. It's by far the most complex role and also, perhaps for that very reason, the most believable. Bouajila embraces the contradictions, possibly realising, as Heath Ledger proved so memorably in Brokeback Mountain, that struggles with sexuality can produce compelling drama.

Les Temoins is well edited, photographed and, on the whole, well directed. The influence of Truffaut's Jules Et Jim is all-pervading, but it's none the worse for that. The film's biggest advantage is that it tackles its subject in an entirely unsentimental way: the same script made in Hollywood would undoubtedly turn into something unspeakably gooey - the memory of Philadelphia, with which it could all too easily be compared, makes me shudder. Les Temoins is way, way above that.