What distinguishes Rodriguez from other action directors, what keeps his films from descending into the indistinguishable blur of a Michael Bay opus, are the funny or melancholic little riffs he weaves in between or in the very middle of his set-pieces. Here, American government cash is handed over to informers in a Clash of the Titans tie-in lunchbox; a gunslinger dressing for battle puts his gloves on the wrong way round by mistake; and there's the lovely image of Banderas and Hayek getting married whilst in shackles, and only then throwing off the chains.
Admittedly, the plotting remains wholly ramshackle - merely a number of recognisable faces circling one another until somebody pulls out a gun and starts firing - and this Once Upon a Time... has little of the mythic poetry of the Leone films to which the filmmaker clearly aspires. Compensation arrives, however, in the form of the real weirdnesses the narrative keeps heading into - a His Kind of Woman-like sidebar finds Depp having his eyes poked out by a man wearing someone else's face, forcing him to rely on a small child to guide him through the rest of the film - and strong work from those whose bodies seem initially to be there solely to fly or skid around the sets.
Mickey Rourke is shaping up very usefully once more, this time as a paunchy character actor in the John Heard/James Woods mould, and there's a surprisingly affecting turn from Ruben Blades as a former FBI agent brought back into service: he Tipp-Exes the "INVALID" from his badge, and spends most of the investigation talking to himself in the absence of any back-up. Depp - whose performance in Pirates of the Caribbean, for better or worse, came to summarise that movie (big, loud, self-consciously "colourful"; altogether too much in a film becoming increasingly conventional) - here hits exactly the right note, whether swearing at children or bearing the logo of the Cleavage Inspection Agency. Rodriguez, for his part, is now making consistently better bullet ballets than the John Woo of the last ten years. One character in Once Upon a Time... poses the question "Are you a Mexican or a Mexican't?" With this director, there's only one answer.
Once Upon a Time in Mexico screens on five tomorrow night at 11pm.