Adapted from a play by Tracy Letts (who also wrote the screenplay), William Friedkin's Killer Joe is not for the prissy; it's a film that is deeply offensive on some levels, which, of course, makes it that bit more appealing. The comedy is served as black as is able within what is, admittedly, a relatively tame premise, the film packing a punch, simmering its violence almost constantly beneath the surface.

Set around a dysfunctional, trailer-trash family, that premise sets itself up very quickly, as Chris, a small-time drug dealer with a large debt he cannot pay, crashes into his father's trailer. He's been kicked out by his mother—for quite probably having assaulted her—and, having heard that she holds a $50,000 life insurance policy, decides he wants to hire the services of Killer Joe, a bent detective who moonlights as a hit man. Ansel, his father, insists on a share, and they contact Joe, who will only do business with payment upfront. This they do not have, but Joe has spotted the demure, virginal Dottie, Chris' younger sister, and is willing to have her as a retainer until the job is done and the money has materialised. Naturally, things don't quite go according to plan.

It's a twist that is easy to see coming, however Killer Joe would always be a fun, quirky little number due to a knowing, clever script. Populated by amoral characters—even the innocent Dottie remarks that the plan to kill her mother is "a good idea"—they quip and tease throughout, and the timing is good enough to create an almost lighthearted feel, despite the murderous subject matter. But the performance from Matthew McConaughey as the titular character is what truly elevates the film. Joe is a coiled spring to be feared and the actor conveys this almost instantly, exuding a casual detachment that complements a tension we are aware will explode violently. When it does in the final act, McConaughey manages to convincingly retain this laid-back sense, and a sexual assault that is at first amusing gradually feels slightly disturbing as Friedkin insists on seeing the act out. This is a wise move as it underlines that this is normal behaviour for the character, and the viewer can only ponder just how extreme the violence is going to get, as McConaughey continues to almost amble his way through it. Ultimately this violence is not extreme at all, of course, but the tension is meted out so effectively that this really isn't a concern, the comedy having satisfied along the way.

Really, there is little to criticise here. The tiniest of hints at a supernatural element to Dottie's character makes for a slightly frustrating red herring, and the climax itself is abrupt to say the least. But these are small complaints. Killer Joe is one of the better releases this year, even more so for knowing just how much it has offended some viewers.

NAILA SCARGILL

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