Darren Aronofsky initially wanted the three main heroin addicts featured in the film (Harry, Marion, and Tyrone) to be much younger than they were in Hubert Selby Jr.'s novel and screenplay. Aronofsky felt that changing the principal characters' ages to around 14 to 16 would further demonstrate the devastating impact of drugs and lead to a greater emotional reaction from the audience. Selby agreed with the director, however the film's producers felt that American audiences would find the film too horrific if young teenagers were to experience such awful events. Selby and Aronofsky lobbied for the characters to be made younger, but producers argued that the film could not be shown in theaters if the protagonists were made out to be teens. Selby acquiesced to the point, but Aronofsky only reluctantly agreed to continue the project with the older characters.