- Genius Bonus:
- Patrick gives detailed descriptions of each character's clothes, including brand names and prices. Readers who are extremely knowledgeable about 80's fashion will notice that the outfits are clownishly mismatched.
- There's a similar gag involving the food at the various restaurants, which go from outrageous but plausible (red snapper pizza) to outright inedible (mud soup and charcoal arugula).
- In the film there's also "peanut butter soup". You don't have to be a genius to be weirded out by that one (peanut soup, sometimes using peanut butter to speed up cooking, does exist though— and is quite tasty).
- Technology Marches On: Patrick's state-of-the-art home entertainment toys seem a bit quaint when read now.
- Write Who You Know: Ellis has described Bateman as being based on his father.
- Actor Allusion / Actor-Shared Background: Technically an Actor/Writer allusion.
Elizabeth: I'm not a lesbian! Why would you think that?Patrick: Well, you did go to Sarah Lawrence.
(Guinevere Turner (who plays Elizabeth) is a lesbian, and really did go to Sarah Lawrence.)
- Dyeing for Your Art: Christian Bale worked out constantly to achieve the buff, narcissistic look a person like Bateman would have.
- Fake American Psycho: Christian Bale, a Wel-English actor, played Patrick Bateman in the film.
- Hey, It's That Guy!:
- Visible Boom Mic: One casts a reflection off of a CD case in Bateman's office during his 2nd meeting with Detective Kimball.
- What Could Have Been: