If you’ve been unsuccessfully fighting a Friday night addiction to KFC, go and see Exorcist director William Friedkin’s new crime-drama Killer Joe for a dose of aversion-therapy that may well do the trick.

The director who brought us that crucifix scene gives a starring role to a KFC chicken leg this time round – and it definitely wasn’t for the sake of product placement. At least I hope not.

An adaptation of playwright Tracy Letts’ play of the same name, the film is on the comical end of the crime-drama spectrum. That said, comedy doesn’t get much blacker than it does here.

The story goes something like this. When a young man named Chris (Emile Hirsch) gets into debt with the kind of people you don’t want to be owing money to, he and his father Ansel (Thomas Haden Church) hire a hit man known as Killer Joe to bump off Chris’ allegedly rather nasty Mum and get her life-insurance pay-out.

The problem is, Killer Joe wants half the money in advance and Chris is broke. So he uses his hot but not-so-switched-on sister, the aptly-named Dottie (Juno Temple), as a ‘retainer’.

The other problem is that Chris and his Dad are both men of epic stupidity. Ergo they soon find themselves way out of their depth with the hit man, played by Matthew McConaughey as you’ve never seen him before – a calm, collected, not-quite-charming psychopath with a strange soft spot for Dottie’s innocence as well as her more salient personal charms.

Throw in a manipulative step-mother (Gina Gershon) and you’ve got all the ingredients for a serious mess.

With its line-up of family betrayals and all-round double-crossing Killer Joe could be high tragedy, but there’s a streak of grotesqueness running through it that makes it feel more like a punch in the solar plexus than a wrench on the heart-strings. By keeping their distance from the material, Friedkin and Letts see to it that there’s plenty to laugh at but no one to really warm to, except maybe Dottie. Saying that, the performances are excellent all round.

As the ‘wicked’ step-mother, Gina Gershon could have been the behind-the-scenes villain of the piece, but she meets her match in McConaughey’s Killer Joe and the two actors generate some interesting chemistry together.

Only at the end does everything unravel a bit too chaotically for the film to hang together. It’s not that the ending doesn’t make sense – not with people as out of control as this lot are – it’s more that you could find yourself so exhausted by everything that’s gone before that you don’t really care.

Released in UK cinemas on Friday 29th June 2012 by Entertainment One UK.

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