The financial success of any film is linked, as Hollywood can attest, to an innumerable number of ways to screw up what was a decent script. The lighting was maybe a little off, or the romance didn't crackle, perhaps the marketing strategy was weak and it was up against that $300 million tsunami romp set in outer space.

A good film, however, is something else. A good film is reliant on the actions and words that jump off the writer's page and on to the big screen - in other words as Hitchcock famously decreed: 'the script, the script, the script'. Very rarely, you will notice, does one overhear a cinema-goer say 'that would've been good Geoffrey, if only the director had chosen a slightly less confrontational angle'. The series of choices that constitute a good film as opposed to a successful film are taken right at the start.

Unfortunately for director Michael Winterbottom (A Mighty Heart, 9 Songs, 24 Hour Party People) and his screenwriter John Curran, the choices for The Killer Inside Me, adapted from a Jim Thompson novel, could not have been more wrong.

The story, set in 1950s Texas, follows Deputy Sheriff Lou Ford (Casey Affleck) who is tasked with removing alluring prostitute Joyce (Jessica Alba) before she causes a scandal with Elmer, the son of the wealthy and influential Chester Conway (Ned Beatty). Unable to resist Joyce, she and Ford begin a sado-masochistic relationship which unleashes repressed memories from his childhood and triggers psychopathic tendencies. One thing leads to another, and Ford is left trying to cover the trail of two dead bodies. Yet despite all his cunning, the investigators never seem too far behind.

You might think, perhaps, that there is potential here for an exciting noir thriller set in reverse - sort of a Dexter meets Chinatown. Unfortunately, with the exception of a sliver of dramatic scenes, the story plods along at a monotonous pace with all the intrigue of a sleeping slug, and dialogue seemingly out of Huckleberry Finn. The story unravels itself in a confusing manner, with a couple of flashbacks that seem relevant but don't fully explain themselves. It's an agonizing struggle, and one which is not helped by a mediocre performance by Affleck who is never able to show us inside the mind of a particularly complex character - a problem considering that the whole film rests on this necessity.

It is a shame also that two real acting talents in Alba and Kate Hudson - who plays Affleck's wife - are reduced to numerous and largely unnecessary sex scenes that add little to our understanding of Affleck's character. The lack of drama is punctuated occasionally by moments of shocking violence that seem unnatural and unnecessarily brutal, and to top it all off there is the most embarrassing and coincidental plot twist ever to grace cinema, plus an attempt to break the fourth wall, which is miserably abrasive.

Winterbottom himself unwittingly gives the most damning indictment of all: "Most of the dialogue is taken directly from [Jim Thompson's] book. It operates almost in a staged way. So the story unfolds through these quite long, formal dialogue scenes...you need actors good enough to pull this off."

A perfect example of how not to adapt a successful book. Why anyone chose to distribute this is beyond me.

Written by Ben Lamy