The Classification and Rating Administration (CARA) had assigned the movie the NC-17 rating for "graphic aberrant content involving violence and sexuality, and a scene of brutality." In the appeal brought by LD Entertainment, the Appeals board heard statements on behalf of "Killer Joe" from David Dinerstein, president of LD Entertainment, and Letts, playwright and screenwriter. The Classification and Rating Appeals Board upheld the NC-17 rating.

William Friedkin directed the motion picture for Voltage Pictures. Playwright Letts also penned the screenplay.

Killer Joe is the story of a dysfunctional Texas trailer-park family: son Chris, who needs quick cash to pay off a drug debt; his father Ansel, who's in no position to help him; his manipulating step-mother; and his innocent sister Dottie. Chris' real mother has stolen the only "assets" he has, leaving him only one way out, until Killer Joe enters the scene.

Playwright Letts is also the author of the Tony and Pulitzer Prize-winning August: Osage County as well as Superior Donuts and Bug.