Personally, I think this does for Matthew McConaughey what Pulp Fiction did for Travolta. Remember when Travolta was lost in Look Who's Talking Hell? Well Matthew McConaughey's been sleepwalking through Romcoms for years. He was great in Dazed and Confused... Remember that?
Well, in Killer Joe he plays a great character, a twisted contract killer with own weird sense of moral purpose. Hired by a couple of dim rednecks to off a family member for the insurance pay out, he waives his usual payment upfront rule and agrees a deal with the drug dealer who hires him. He'll take the dealers trailer park ingenue sister as a retainer instead until the cash comes through.
In a cinematic landscape of bland, safe big screen entertainment, this is the kind of underbelly darkness that really bites. Blackly comic, expertly played and building to a shocking climax, Killer Joe is a must see movie.