Close but no cigar. This is an entertaining cop melodrama with a dash of Gallic style. Yet it might have been the heir to Dassin’s Rififi or Clouzot’s Wages of Fear. Its set up has the ingredients. But Marchal has taken the safe route to journeyman melodrama rather than edge of the seat, morally ambiguous, definitive crime drama.

Though exciting in parts it falls prey to the modern belief that tension is a function of noise and weaponry. The cold dead hand of Hollywood I fear. Marchal, unlike Jacques Audiard in The Beat That My Heart Skipped, the best French crime drama of recent years, slides into a mid-Atlantic cop saga which takes away the distinctiveness of the Paris setting and the special moral ambiguity of the French ethos.

Rightly compared with Micahael Mann’s good, but over-praised, Heat, 36 falls short for exactly the same reason. Simple but fundamental. Both films offer the excitement of on-screen confrontation between major box office stars: Pacino and De Niro and now Auteuil and Depardieu. And astonishingly for me, both get the central casting decision fundamentally wrong. In my view Heat would have been as exciting as its publicity hype claimed had Pacino and De Niro reversed roles. I accept that casting against type can sometimes work but for me Depardieu and Pacino are always the instinctive rebels and Auteuil and De Niro the instinctive conformists. “Travis Bickle” (De Niro - Taxi Driver) I hear you say. But Travis Bickle is not an anarchist dissident from conformist values – he is a Nazi with no Reich. The proper order of the world has been taken over by liberal chaos.

And so with Depardieu. My hunch is that Pacino and De Niro tossed a coin. But I suspect Auteuil’s current box office appeal in France outplayed Depardieu’s past glories. So Auteuil gets street cred and a cool persona, while Depardieu (Denis Klein) is locked into a part about two sizes too small even for his obviously newly dieted frame. This fundamental miscasting undermines any serious aspirations the movie may have begun with. And provokes the thought that star names are not necessarily sound judges of the best deployment of their talents.

Auteuil’s Leon Vrinks is old school cop. Honest, committed but morally pragmatic at the edges. The criminal fraternity adheres to certain implacable values eg snitches get done. Auteil’s Leon gets drawn into this group ethic by the need for definitive inside information. When informants break an implacable code their protection becomes a pragmatic necessity. He is tricked into witnessing his informant, Silien, executing the guy who sent him down. Then Silien trades the names of a murderous gang of serial robbers in return for Vrinks alibiing the murder. A neat device – he can’t get clean, so he uses being dirty for a good purpose.

The acid test of any drama is – does character drive plot or plot drive character? Real depth rests on the first although many superbly entertaining movies follow the second. Opaquely it emerges that Leon’s wife Camille is an ex-love of Klein’s. Also Leon is smarter and better respected by his men than the pedestrian, clumsy, alcohol-fuelled Denis. But Klein ticks the establishment boxes and so inevitably advances in his career. The personal and moral conflict that is the dramatic epicentre of this movie is dissipated by the miscasting. While Auteuil could play either part, Depardieu could only convince as Vrinks. As Klein his own lack of conviction in the part cardboards the character. Klein's personality doesn't let Depardieu play. When Klein blows a Vrinks-led ambush, leading to the death of Eddy, Vrinks’s right-hand-man, his actions seem just plain stupid not simply a bad call bred of ambition or jealousy. It is frustrating to see such a promising set up wasted through lack of rigour in integrating character and plot. So at times 36 loses dramatic tension though drifting into melodrama. Maybe the stars cost too much money to properly hone the screenplay.

Klein learns of Vrinks’ compromised deal and shops him, leading to his imprisonment. Vrinks’ evidence against Klein’s actions at the ambush thus disallowed, Klein is exonerated and promoted. Vrinks is jailed. Trapped between this inter-personal rivalry is their boss Dusollier (Robert Mancini), chief of Police designate. Dusollier’s heart and cop instinct is with Vrinks, but his head conforms to internal police politics. A suave, morally ambivalent role Mancini does superbly. In a triumph of authoritarian managerial blindness of which perhaps only the French establishment are capable, Klein is promoted to the job everyone wanted the disgraced Vrinks to have. One of Vrinks’ men, the off-the-wall Titi offering his congratulations at a formal celebration of Klein’s promotion, by peeing down his new boss's back. Titi leaves the party and the force. But he gets his own back.

Klein maintains surveillance on his lost love Camille, now Vrinks’ wife. When she meets with the fugitive Silien, Klein, through operational pig-headedness precipitates a car crash that kills both Camille and Silien. Thus that most satisfying of movie drivers, revenge, fuels the conclusion to 36. This is entertaining enough but again loosens its grip on credibility through some lazy plotting. (One element of this, supposed to heighten the tension between the protagonists, still really makes no sense to me). For example, Vrinks gatecrashes without challenge, gun in pocket a formal police gathering by flashing a 7 year-old, rescinded police pass.

The movie’s ending is neat but predictable. It works well enough but I cannot help but feel that Marchal falls disappointingly short of his own aspiration. Potentially a fascinating mix of moral ambiguity, ambition and entangled passions within an exciting crime drama, it settles for a neatly wrapped, tidy package. A bit like a gift in a window display – it looks convincing but when you open it, there is only wrapping – nothing inside.