Answer
"The Collector," a 1965 British psychological horror film, served as a significant influence on the crimes committed by Dennis Rader, also known as the BTK (Bind, Torture, Kill) serial killer. The film's portrayal of a psychopathic serial killer who abducted and held victims captive in his basement, subjecting them to torture and psychological torment, resonated deeply with Rader's own criminal tendencies and fantasies.