Directed by Martin McDonagh. Starring Colin Farrell, Sam Rockwell, Woody Harrelson, Christopher Walken, Tom Waits, Abbie Cornish, Zeljko Ivanek, Gabourey Sidibe, Michael Pitt 16 cert, general release, 110 min

Despite its flaws, Martin McDonagh's funny post-modern follow-up to In Bruges suggests he's here to stay, writes DONALD CLARKE

You have to worry a little when a movie looks to be making post-modern excuses for itself. Martin McDonagh’s hectic, very funny follow-up to In Bruges concerns a Hollywood scriptwriter (granted all the boozy clichés) who is failing to compose a screenplay named, yes, Seven Psychopaths.

At various points in the picture, we stop to consider what is wrong with the hero’s version of Seven Psychopaths and, inevitably, find ourselves pondering issues concerning McDonagh’s version of the story. Are the female characters underdeveloped? Perhaps. But that is the case with many mainstream productions, and McDonagh’s film is, among other things, a comment on malaises of modern cinema.

At no stage does any character glance alongside the main problem with the real film. After a cracking opening hour that jumps and starts with great invention, McDonagh’s characters leave LA and drift into a much less interesting, much less self-conscious picture. Ending as an accidental take on Raoul Walsh’s High Sierra – complete with canine sidekick – Seven Psychopaths comes across as a picture with insufficient oil in its tank.

That fine beginning bears favourable comparison with similarly playful scripts by Charlie Kaufman. Marty Faranan (Colin Farrell) lives unhappily in a glossy, sun-bleached corner of Los Angeles. He is struggling hard with Seven Psychopaths, but can’t quite get any proper purchase on the project. Given the colourful penumbra of maniacs that surround Marty, it’s faintly surprising that he has even found time to devise the excellent title.

Marty’s best pal, Billy (Sam Rockwell), is supportive, but slowly emerges as sufficiently dangerous to secure a place in the script (which, in a sense, he does). Elsewhere, an untouchably urbane Christopher Walken conspires with Billy in a plot to steal dogs and flog them back to their desperate owners. Perhaps inevitably, they end up falling foul of a comically violent gangster (the aggressive version of Woody Harrelson) and find their uneasy equilibrium shattered.

It is hard to avoid comparisons with Pulp Fiction. In Bruges, eventually a cult hit, was, like Tarantino’s Reservoir Dogs, a disciplined, tight affair featuring indulgent slabs of gorgeously quotable dialogue. Both director’s second films expanded the scope and narrative complexity.

McDonagh has found the characters and the actors to exploit his larger palette. Walken has rarely been better (and that’s saying something). His carefully spoken sage has a mild hint of madness about him, but – decked out in a smashing cravat – he is also allowed moments of genuine poignancy. Rockwell manages to be both charming and troubling in the course of the same sentence. Farrell again demonstrates that his natural milieu is weird pulp rather than lumbering blockbuster. Tom Waits does what he does.

At times, the galloping absurdity drifts into off-the-peg comedy gangster cliché. But McDonagh’s brilliant way with one-liners always claws back enough ground to stifle any groans. We appear to be watching a playwright working hard to prove that he understands the meaning of the word “cinematic”.

Then, sadly, the film starts to wind down towards its oddly low-key, somewhat hurried denouement. The last act might, perhaps, have worked better as part of a more conventional film. As things stand, we are left with a somewhat broken-backed enterprise.

Seven Psychopaths is, however, more than tasty enough to persuade us to look forward to McDonagh’s next piece with eager enthusiasm. He’s here to stay.