When Bateman in the end of the movie confesses his murders to the answering machine, he mentions murders like a man with a dog and a girl with a nail gun. Those are all murders described very graphically in the book.

In Detective Kimball's questioning Bateman, Bateman mentions that he has a lunch with Cliff Huxtable in 20 minutes. Cliff Huxtable was the name of Bill Cosby's character on "The Bill Cosby Show," a popular series on at the time of the story. Furthermore, Kimball mentions that a Hugh Ainsworth spotted Paul Allen in London. Hugh Ainsworth is a popular crime author.