Based on a novel by Jack Ketchum, 2007's harrowing The Girl Next Door movie is made a much harder watch after learning about the Girl Next Door true story. Both the movie and the book were inspired by the real-life case of Sylvia Likens and Gertrude Baniszewski. While the '00s had no shortage of extreme 'torture-porn' movies, The Girl Next Door is renowned for the exceptional level of cruelty it portrays, and how difficult it is to watch — and the real story that inspired The Girl Next Door makes it even harder to sit through.
https://screenrant.com/girl-next-door-movie-true-story-harder-watch/