Directed by Nicolas Klotz. Starring Mathieu Amalric, Michael Lonsdale, Edith Scob, Lou Castel, Delphine Chuillot, Jean-Pierre Kalfon Club, IFI, Dublin, 143 min  ***

IF EVER a film creaked beneath the weight of its ambition, it would be this strange, sleek corporate thriller from France. Mathieu Amalric, so good in The Diving Bell and the Butterfly, stars as a psychologist at a petrochemical firm who uncovers terrible truths - some conspiratorial, some personal, some merely metaphorical - when investigating the unusual behaviour of the company's CEO.

Occasionally somewhat dull, though never less than striking, Heartbeat Detectorcomes across like a blend of Hiroshima Mon Amourand Michael Claytonforced through a sieve manufactured by Jean-Luc Godard. It really is that odd.

Amalric's Simon Kessler, a dry, methodical man, discovers that his subject, Mathias Jüst (the reliably charismatic Michael Lonsdale) was once in a string quartet and was unusually depressed by the group's dissolution. Jüst then reveals that Nazi sympathisers raised Kessler's immediate superior (the man who commissioned the investigation) as a racially pure superchild. Between his attempts to fit these revelations together, the hero courts various women and cavorts at latenight rave parties.

The film's most ambitious sections dare to suggest comparisons between Kessler's cool decisions about the worth of various employees and the Nazi's more calamitous calculations concerning the annihilation of France's Jewish population.

This is dangerous territory, but Nicolas Klotz, director of 1988's La Nuit Bengali, and François Emmanuel, whose first feature script this is, allow the connections to emerge in a subtle, tasteful fashion. The sequence in which Kessler uncovers the Nazis' methodical description of the best practice for murdering Jews conveys volumes about the way corporate euphemisms can obscure terrible realities.

Yet, for all the originality of the film-makers' approach, it can't be denied that long sections of Heartbeat Detectorare deathly dull. Including one musical interlude might be seen an acceptable indulgence, but allowing three such extraneous sequences really strains the patience. The romantic subplot is puzzling and every conversation goes on five minutes too long.

Still, it is the wilful nature of the project that helps it stand out from the pack. For good or ill, this is one of a kind.

DONALD CLARKE