About three-quarters of the way through Killer Joe, the terrific and cheerfully evil film opening this Friday, Matthew McConaughey pointedly, if seemingly absently, picks up a chicken leg from a bucket of KFC. You might not realize it at the time, but this is the Chekov's Gun of chicken legs. This is a chicken leg that's definitely going off in the third act.
I'm not going to give away what happens with the chicken leg other than to say that it's the primary (though not only) reason Killer Joe is rated NC-17 and that it's more horrifying and perverse and hilariously insane than anything you can possibly imagine Matthew McConaughey doing. McConaughey received a lot of well-deserved praise for his supporting work in Magic Mike—he treats his final dance sequence like it's some sort of erotic, oddly sad career eulogy—but it has a been a long time since a performance actively surprised me as much as McConaughey's does in Killer Joe. In Magic Mike, McConaughey is essentially channeling Tom Cruise's Frank "T.J." Mackey; in Killer Joe, he's doing something crazier, and more balls-out. Every movie star likes to play the bad guy every once in a while to shake it up, from Tom Hanks in Road to Perdition to Harrison Ford in What Lies Beneath to even George Clooney in The Ides of March. But they always leave their flank protected: They'll never go, in the nomenclature of Robert Downey Jr. in Tropic Thunder, Full Evil. But McConaughey goes Full Evil and then some: He goes Full Sadistic Twisted Sex Fiend. And what's amazing is not only that you buy it, but how defining it is: After seeing Killer Joe, you'll never buy McConaughey in a romantic comedy again, at least one not involving one or several human centipedes.
Killer Joe starts out as a typical, albeit well-done, crime thriller, before everything goes off the rails. A family of trashy Texans—played with teeth-rotting devotion by Emile Hirsch, Gina Gershon, and Thomas Haden Church—decides to pay off a mob debt by murdering the estranged matriarch. They don't know what they're doing though, so they stumble across a cop who makes some side cash by murdering people, the Joe of the title, played by McConaughey. But he's far more interested in the family's teenage daughter (played by Juno Temple, whom you might recognize as Catwoman's "friend" in The Dark Knight Rises), a sweet-hearted, semi-mush-brained innocent who is more comfortable hiding in her room with her dolls than interacting with these crazies. He decides to take the daughter as collateral in case the family can't pay his fee—it'll come as little surprise to learn that they can't—and then all hell keeps breaking progressively looser and looser.
The movie is gross and smutty and has a sticky film on it that just won't rinse away: It is having so much fun portraying terrible people doing terrible things to one another that it has no interest in pausing to think about what any of this means. But director William Friedkin, that old master who brought us The French Connection and The Exorcist before a few decades in the wilderness (the man directed Blue Chips, for cripes sake), shows off a dirty old man's glee; the movie is almost affably amoral. In that way, it has a lot in common with Sidney Lumet's Before the Devil Knows Your Dead, another film directed late in life by an old Hollywood legend who had nothing to prove to anybody anymore. But Killer Joe is willing to go further than that film ever did, while still staying grounded in recognizable human behavior. You won't believe what the characters in Killer Joe do to each other. But you'll believe that they're capable of it.
And at the center of it all is McConaughey, who's the worst of them all, but also the most capable, the only one in the movie who is wily and intelligent enough to win every battle. That's what makes him so terrifying: The most evil person in the movie is the smartest, and everyone in his way is an easy mark. Except for that teenage girl: That girl is his weakness, just like—one suspects countless girls—were before, before he dispatched them and their families for standing in his way. It's a legitimately brave performance. I don't remember the last time a big-time actor went full freak like this. (He's about one step removed from "put the biscuit in the basket," honestly.) I hope I haven't made the movie seem like a dark slog or anything. The movie is a romp in every possible way. It just happens to be an evil one. It would earn its NC-17 even without its more extreme scenes; this one should get an NC-17 for its attitude alone. That's a reason to love it even more though. Let's chalk one up for the bad guys for once.
But seriously: Beware that third-act chicken wing. You've been warned.
Grierson & Leitch is a regular column about the movies. Follow us on Twitter, @griersonleitch.