explain – though not justify – the devastating behaviour that is a serial killer." D'Onofrio was drawn to the project by Lynch's involvement, as he had wanted to work with her on Boxing Helena. Lynch had also wanted to work with D'Onofrio, but the role was not specifically written for him. Lynch was drawn to D'Onofrio, who was always her first choice, because the part required an actor that was capable of showing an injured inner child. Because D'Onofrio was willing to do this, Lynch praised his performance as brave. Farren and D'Onofrio worked well together on the set, which D'Onofrio credits for their on-screen chemistry. The actors used very little improvisation. For Bob, D'Onofrio said that he needed to find the character's moral compass, even though Bob is a serial killer. As a character actor, D'Onofrio said that he is drawn to fascinating characters, no matter how flawed. Farren was impressed with Lynch's cover letter for the script reader and got along very well with her when they spoke. On set, Farren and Lynch collaborated easily, and Farren said that she did not need to give much direction to him. Lynch recruited Bird, who played the young Rabbit, over Skype after the casting crew recommended him. Lynch said that his audition tape gave her chills. The film is a study of how monsters are made, and Lynch says that she wanted to "promote a dialogue about child abuse." Through Bob's back story, Lynch attempted to show how society had turned him into a monster through child abuse. With Rabbit, she wanted to explore the theme of "nature vs nurture". Farren described Rabbit as a stunted child, a nineteen-year-old man who stopped emotionally maturing at nine. Rabbit did not become what Lynch called "a full blown replica of Bob" because he has a loving childhood. This allowed Lynch to compare and contrast how the two men turned out. Lynch did not want to perpetuate the cycle of violence and make Rabbit into a killer, which she said would have been boring. Lynch was contractually obligated to keep the film to a certain run time, so she had to abbreviate the plot twist. Although she recognizes that some people find it to be tacked on, she said that a director's cut would expand on it and make it more natural. The ending scene is meant to be hopeful, and Lynch says