Wannabe small-town Texas drug-dealer Chris (Emile Hirsch) owes his ruthless connection several thousand dollars. However, he can't scrape up the funds in the usual manner, as his supply has vanished up the nose of his vile mother, Adele. Aid is not forthcoming from his drunken dimwit of a father, Ansel (Thomas Haden Church), now married to viper-tongued middle-aged sexpot Sharla (Gina Gershon) and doing a poor job of parenting Chris' sister, Dottie (Juno Temple), a trailer-park waif who is a little touched in the head. Chris' only remaining gambit, as he explains to Ansel, is to hire a hitman to murder Adele, whereupon they can divvy up the spoils of her sizable life insurance policy, to which Dottie is apparently the sole beneficiary. Enter “Killer” Joe Cooper (Matthew McConaughey, a notch to the left of his usual role): a Dallas police detective who moonlights as a killer-for-hire, and cultivates an appropriately menacing, laconic manner beneath a black Stetson. Of course, Chris can't meet Killer Joe's up-front payment, but the hitman explains that he would accept a non-cash retainer, a proposition made with a leering eye directed at Dottie.
From there, the events of Killer Joe take all manner of repulsive and absurd turns, descending into a bloody, gurgling stew of criminality and retribution. Adapted from the stage play of the same name by Pulitzer-winner Tracy Letts, the film is an amusingly loathsome dip into the kind of lurid, borderline-ludicrous material that veteran filmmaker William Friedkin is unable to resist. In the nearly 40-year wake of the stupendous one-two punch of The French Connection and The Exorcist, Friedkin's career has been erratic, but his 2007 adaptation of Letts' play Bug is an under-appreciated achievement, serving as both the director's best film since 1985's To Live and Die in L.A. and a high-water mark for actress Ashley Judd. Friedkin's second collaboration with Letts—who penned the screenplays for both films—is less successful, in part because the director's handling of Killer Joe's “redneck-Gothic” tone and coal-black humor is at times awkward.
The film's broadly comic moments—exemplified by Church's splendid, hang-dog performance—are a genuine pleasure, and the menace that Friedkin evokes from scenes of confrontation and confession is gratifyingly nerve-wracking. However, when the script calls for a knife's-edge balance between the ridiculous and the horrifying, the director often errs clumsily in favor of one or the other. Killer Joe has a deeply discomfiting story, replete with sexualized violence and moral disorder, where the only likeable character is a woman-child who is casually victimized by her loved ones. Such a film demands both a keen eye for the repulsive and masterful tonal discipline, and Friedkin only intermittently pulls off this dual feat. The director manages to keep the proceedings humming along primarily on the strength of his performers and the momentum of the script's lengthy scenes, which vibrate with ugly, remorseless energy. Be warned: It goes without saying that a film where a battered, bloody woman is forced to... service a fried-chicken drumstick is not for the faint of heart.