EXPECTATION

REALITY

The film received negative publicity in 1974 when it was discovered that the scene where the prostitute is killed with drain cleaner had allegedly inspired the infamous Hi-Fi Murders, with the two killers believing the method would be as efficient as it was portrayed in the film. The killers said that they were looking for a unique murder method when they stumbled upon the film, and that - had they not seen the movie - would have chosen a method from another film. The drain cleaner reference was repeated in at least three other films, including Lethal Weapon (1987), Heathers (1989) and Urban Legend (1998). According to scriptwriter John Milius, this drain cleaner scene was never meant to be filmed, but was only mentioned in his original script.^[5]

(from Wikipedia, under controversy)