<P> Meanwhile, Doyle becomes increasingly abusive towards Karl and Frank, leading to an eventual drunken outburst and physical confrontation with Linda and Frank, angering the boy . Linda then kicks Doyle out of the house (despite his threats to kill her if she ever left him). A few days later, 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, eventually, either Frank is going to kill Doyle and end up just like him or that Doyle's abuse will end up killing Frank and Linda . In order to prevent this, 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 . </P> <P> Karl returns to Linda's house, but seems undecided about whether to enter . When confronted, a drunk Doyle asks what Karl is doing with the lawnmower blade he had sharpened and fashioned into a weapon . Karl replies, "I aim to kill you with it," but not before asking how to reach the police by telephone . Not taking Karl seriously, Doyle says he should dial 911 and request "an ambulance, or a' hearst' ." Karl kills Doyle with two chopping blows of the lawnmower blade to the head . Karl then phones the police to turn himself in, and requests a "hearst" be sent for Doyle . He eats biscuits while waiting for the police . </P> <P> Returned to the state hospital, he seems a different person than he was during his previous incarceration, having learned the value of sacrificing one's self to save others . He silences a sexual predator (played by J.T. Walsh) who had previously forced him to listen to tales of his horrible deeds . </P> <Ul> <Li> Billy Bob Thornton as Karl Childers </Li> <Li> Dwight Yoakam as Doyle Hargraves </Li> <Li> J.T. Walsh as Charles Bushman </Li> <Li> John Ritter as Vaughan Cunningham </Li> <Li> Lucas Black as Frank Wheatley </Li> <Li> Natalie Canerday as Linda Wheatley </Li> <Li> James Hampton as Jerry Woolridge </Li> <Li> Robert Duvall as Karl's father </Li> <Li> Jim Jarmusch as Gene, the Frostee Cream employee </Li> <Li> Vic Chesnutt as Terence </Li> <Li> Brent Briscoe as Scooter Hodges </Li> </Ul>

What happens at the end of sling blade
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