Sicario: the slick mayhem of secret drug wars | Cannes review

It is probably appropriate (indeed, deliberate) that Denis Villeneuve's gripping thriller concerning the war on drugs should end in murky confusions. The ancient shadow conflicts of the Cold War seem positively straightforward when set beside the lies and switchbacks that characterise the conflict in Sicario.

Named for a Mexican slang word for hitman, the film stars an intense Emily Blunt as an FBI agent brought on board by the CIA – for bureaucratic reasons that are revealed halfway through – to assist with quasi-legal cross-border operations. The plot is squeezed out during taught, barked exchanges between a morally conflicted Blunt and the less reticent male agents. Josh Brolin swaggers as the head spook. Benicio del Toro remains psychologically hooded as an independent operative seeking a degree of revenge.

The characters are, perhaps, a little too emblematic. Blunt could hardly be a more obvious "eyes of the audience" type if she had those words plastered on her increasingly soiled tee shirt. Happily, the actors are sufficiently imaginative to inject real character into the near-stereotypes. Happily, rather than turning Blunt into an invincible Amazon, they allow her a degree of physical vulnerability.

Villeneuve's film, however, really shines in its violent set-pieces. Scored to disturbing bass throbs by Johann Johannson, photographed with kinetic fury by Roger Deakins, the opening attempt to transport a drug kingpin back across the border is a masterpiece of vehicular tension. There is something of Zero Dark Thirty about the film, but there is much less equivocation here about the rights and wrongs of a secret war. Michael Mann should also see something of himself in the slick mayhem.

The film marks yet another successful step into the edgier corners of the US mainstream before Villeneuve embarks on a proposed Blade Runner sequel. The signs here are good. His recent Captives showed a gift for maintaining tension; Sicario confirms he can also do action.