Sling Blade - Plot

Plot

Karl Childers (Billy Bob Thornton) is a mentally disabled Arkansas man who has been in the custody of the state mental hospital since the age of 12 for having killed his mother and her lover. Although thoroughly "institutionalized," Karl is deemed fit to be released into the outside world. Prior to his release, he is interviewed by a local college newspaper reporter, to whom he recounts the brutal murder of his mother and her boyfriend with a Kaiser blade - during which scene he notes to the reporter that, "Some folks call it a sling blade. I call it a kaiser blade," the line from which the film derives its name. Karl continues, saying that he killed the man because he thought he was raping his mother. When he discovered that his mother was a willing participant in the affair, he killed her too.

Having developed a knack for small-engine repair during his childhood and his institutionalization, Karl lands a job at a small-engine repair shop in the small town where he was born and raised. Around this time, he befriends 12-year-old Frank Wheatley (Lucas Black). Karl shares with Frank some of the details of his past, including the killings. Frank reveals that his father was killed - hit by a train - leaving him and his mother on their own - he later admits that he lied, and that his father committed suicide.

Frank introduces Karl to his mother, Linda (Natalie Canerday), as well as her gay friend, Vaughan Cunningham (John Ritter), the manager of the dollar store where she is employed. Despite Vaughan's concerns about Karl's history in the mental hospital, Linda allows him to move into her garage, which angers Linda's abusive boyfriend, Doyle Hargraves (Dwight Yoakam). Eventually, Karl bonds with both Linda and Vaughan. In an early scene, Vaughan tells Karl that a gay man and a mentally challenged man face similar obstacles of intolerance and ridicule in small-town America.

Karl quickly becomes a father figure to Frank, who misses his father and despises Doyle. For Karl, Frank becomes much like a younger brother. Karl eventually reveals that he is haunted by the task given him by his parents when he was a child of six or eight years: to dispose of his premature, unwanted, newborn brother. In a subsequent scene, he visits his father (Robert Duvall), who has become a mentally unbalanced hermit living in the dilapidated home where Karl grew up. Karl tells his father that killing the baby was wrong, and that he had wanted to kill his father for making him do it, but eventually decided that he wasn't worth the effort.

Doyle becomes increasingly abusive toward Karl and Frank, leading to an eventual drunken outburst and physical confrontation with Linda and Frank. Linda kicks Doyle out of the house, telling him to go home and sober up. The next day, Linda and Doyle reconcile. Knowing that he has the upper hand again, Doyle confronts Karl and Frank and announces his plan to move into the house permanently; he plans "big changes", including Karl's removal from the house. Karl begins to realize that he is the only one who can bring about a positive change and thus spare Frank and his mother a grim fate. Karl makes Frank promise to spend the night at Vaughan's house, and asks Vaughan to pick up Linda from work and have her stay over also.

Later that evening, Karl returns to Linda's house, but seems undecided about whether he should enter. After asking Doyle how to reach the police by phone, he kills Doyle with two stabbing blows to the head from a lawnmower blade he'd fashioned into a weapon. Karl then calls the police to turn himself in, and requests a hearse be sent for Doyle. He calmly dines on biscuits and mustard while waiting for the authorities.

Returned to the state hospital, he seems a different person than he was during his previous incarceration. He sternly rebuffs a sexual predator (J. T. Walsh) who had previously forced him to listen to tales of his horrible deeds.