!!In both the book and movie:
[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/asiq4jj_7.gif]]
[[caption-width-right:350:Rule [[LOL69 #69]] of Patrick Bateman: if you're not having sex in front of a wall-to-wall mirror, you're doing it wrong.]]
* The [[https://www.youtube.com/watch?v=cISYzA36-ZY business card comparison scene]].
-->[''Looking at Paul Allen's business card, which looks virtually identical to every other card in the room'']
-->[[SeriousBusiness Look at that subtle off-white coloring. The tasteful thickness of it. Oh my God, it even has a watermark!]]
** Shortly before Bateman and his peers begin to compare their business cards, Paul approaches Patrick and mistakes him for Marcus. Patrick says that it's logical since both he and Marcus have the same job and the same preferences for clothing and glasses. Bateman then has to stroke his ego by internally boasting about his haircut.
--->"Marcus and I even go to the same barber, though I have a slightly better haircut."
** Not to mention, [[FailedASpotCheck none of them notice that "Acquisitions" is spelled wrong on every business card we see]]. And every single one of them shows each member of the board is apparently Vice President.
* Bateman's mental breakdown teeters the line between hilarious and downright chilling, but manages to stay in the realm of comedy for a prolonged period of time with moments such as the left-field absurdity of "FEED ME A STRAY CAT" and his nonchalant compliance, as well as a moment where he shoots a cop car and becomes bewildered when it [[EveryCarIsAPinto violently explodes]]. The book also has some additional moments of {{surreal humor}} with Bateman seeing a Cheerio being interviewed on TV and a park bench growing legs and chasing him like something out of an early ''WesternAnimation/LooneyTunes'' short.
** One particular moment is the sheer abruptness of when he shoots the desk clerk who confuses him for a "Mr. Smith", runs to a revolving door, goes all the way around and re-enters the building just to shoot a janitor who walked into the lobby, before going around again to exit.
* A scene in the book (filmed but omitted from the movie) features Patrick painfully [[TotallyRadical trying to be hip]] and familiar with a Rastafarian, calling him "Marley" and saying "...yeah, we be jammin'..." to himself after being brushed off.
** Here it is from the book:
--->I stick out my hand at a crooked angle, trying to mimic a rapper. "Hey," I say. "I'm fresh. The freshest, y'know-- like, uh, def-- the deffest." I take a sip of champagne. "You know-- def."\\
To prove this I spot a black guy with dreadlocks and I walk up to him and exclaim "Rasta Man!" and hold out my hand, anticipating a high-five.
* Bryce getting super miffed that some powdered sugar got mixed into his cocaine. ''"We're trying to get high off of it, not sprinkle it on our fucking cornflakes!"''

!!In the book:
* Bateman's red snapper pizza rant in the book is pretty funny too, especially since it comes totally out of left field:
-->"No one wants the fucking red snapper pizza! A pizza should be ''yeasty'' and slightly ''bready'' and have a ''cheesy crust''! The crusts here are too fucking thin because the shithead chef who cooks here overbakes everything! The pizza is dried out and brittle!"
** And then later, when Bateman is forced to eat his words because UsefulNotes/DonaldTrump says he likes the pizza in question.
** Which is in turn HilariousInHindsight when [[Series/TheDailyShow Jon Stewart]] ridiculed Trump for taking UsefulNotes/SarahPalin to a budget franchise pizza place, passing it off to her and her family as "Authentic New York Pizza".
* The chapter where Bateman and his associates are trying to organize a dinner in a restaurant using conference call and mess everything up. By the end, it's night, they still don't have a reservation, Evelyn and Jeanette are in the Kaktus Bar because they were told to meet the men there, and Patrick is so hungry that he is eating cereal out of the box.
* At one point, an associate mentions that one client at a business lunch ordered boudin blanc, roasted chicken, and cheesecake for dessert. Patrick is utterly perplexed that these dishes were so very ordinary, without any weird-ass nouvelle cuisine flourishes like exotic fruits, sauces or flowers mixed in.
* 'I quickly stand, brushing him off, and when I think his outburst has subsided and he's able to walk away, Luis grabs my right ankle and tries to hold on as I'm leaving Barney's and I end up dragging him along for six feet before I have to kick him in the face, while smiling helplessly at a couple who are browsing near the sock department.'
* In the first chapter of the book, Timothy Price (Patrick's associate) is reading a newspaper and commenting on all the terrible headlines:
-->"In one issue... in one issue... let's see here... strangled models, babies thrown from tenement rooftops, kids killed in the subway, a Communist rally, Mafia boss wiped out, Nazis, baseball players with AIDS, more Mafia shit, gridlock, the homeless, various maniacs, faggots dropping like flies in the streets, surrogate mothers, [[ArsonMurderAndJaywalking the cancellation of a soap opera..."]]
* There's a fake TV talk show (think Maury Povich-- or more likely [[https://en.wikipedia.org/wiki/Sally_Jessy_Raphael Sally Jessy Raphael]]) that Patrick regularly watches called ''The Patty Winters Show''. The topics he mentions start out as pretty normal and mundane (Autism), but they quickly descend into nonsense ("Dwarf Tossing" "A boy who fell in love with a box of soap", and "[[TheGreys UFOs]] That Kill"). Later on, when Patrick's lost all touch with reality, the show has [[BigfootSasquatchAndYeti Bigfoot]] on as a guest, who Patrick claimed was "surprisingly articulate and charming", and finally...
-->"On The Patty Winters Show this morning a Cheerio sat in a very small chair and was interviewed for close to an hour."
** One episode seemingly produced ''just'' for Patrick (if it isn't an outright hallucination) is divided between an interview with his personal idol, Donald Trump, and "Women Who Were Tortured."
* Bateman playing with the little daughter of one of his associates, offering her his American Express card: "I'm shaking my head, talking in a high-pitched baby voice, squeezing her chin, waving the card in front of her face, cooing, 'Yes I'm a total psychopathic murderer, oh yes I am, I like to kill people, [[CutenessProximity oh yes I do, honey, little sweetie pie, yes I do...'"]]
* Patrick makes a bunch of obscene phone calls:
-->"I'm a corporate raider," I whispered lasciviously into the cordless phone. "I orchestrate hostile takeovers. What do you think of that?" and I would pause before making sucking noises, freakish piglike grunts, and then ask, "Huh, ''bitch?''" Most of the time I could tell they were frightened and this pleased me greatly, enabled me to maintain a strong, pulsing erection for the duration of the calls, until one of the girls, Hilary Wallace, asked, unfazed, "[[CrossesTheLineTwice Dad, is that you?]]" and [[EvenEvilHasStandards whatever enthusiasm I'd built up plummeted]].
* Along with a teller demanding Patrick "Kill the President!" and "Feed me a Stray Cat", Patrick also hallucinates that a park bench chased him down the street for several blocks. He recounts that with total sincerity.
* Patrick becomes very happy when he manages to buy a box of cereal by paying with an expired coupon. He tries to whistle "Hip to be Square" while he eats them and then proceeds to run up and down the streets, screaming "like a banshee", his open coat flying like a cape.
* In one commercial on TV, a man says to his wife, "Hey, you're right... this margarine really does taste better than shit."
* Patrick giving a dollar to a girl he believes is homeless when at the last minute he finds out she is only a college student when he puts the dollar into her cup of coffee.
* Chapter 20, A Glimpse of a Thursday Afternoon, starts in media res (and in the middle of a sentence) with Patrick at a phone booth having some sort of mental breakdown. The entire chapter is him stumbling around Downtown New York, delirious and panicking. His ways of trying to calm himself include buying rats to torture later (which he forgets at another store), shoplifting a can of ham to eat out of the tin and puking it back up, and finally wandering into a Jewish deli (that he mistakes for a high-class restaurant that he has a reservation for) and trying to order a burger with cheese and a milkshake, only to be told repeatedly that they only serve kosher dishes. He finally gets angry and leaves, with the chapter ending mid-sentence as he continues his delirious journey.
* Bateman revealing off-hand that he hates mimes when he briefly considers killing a clown, but decides against it because he's too dorky to kill.
-->"Though if he'd been a mime, odds are he'd already be dead."

!!In the movie:
* [[https://www.youtube.com/watch?v=vzN3qO-qc8U The scene]] in which Bateman reels off all manner of memorized observations regarding the musical styling of Music/HueyLewisAndTheNews - [[CasualDangerDialog all the while preparing to murder Paul Allen.]]
** Try not to laugh when Bateman ''moon-walks'' behind Paul, who's too drunk to realize what's happening. Right as he finishes talking about Huey Lewis, he gets the axe ready and cheerfully calls out "[[HeyYouHaymaker Hey, Paul!]]" before killing him.
*** The capper is "[[SoundtrackDissonance Hip to Be Square]]" playing over the violent murder, Bateman [[DissonantSerenity acting positively giddy just before the act]], and his [[DissonantSerenity calmly]] lighting a cigar after the act is over, with [[BloodIsTheNewBlack blood all over his face]].
*** Paul's total obliviousness to the red flags that he's about to be murdered and Patrick's enthusiastic admissions to them really sell the absurdity of the entire scene. In particular, when Paul asks if Patrick is wearing a rain coat (so Paul's gore doesn't splash on Patrick's pristine suit), Patrick gives a giddy "Yes, it IS!"
** [[https://www.youtube.com/watch?v=Fk15H6PjBis The Funny or Die parody of this scene]], with Huey Lewis himself as Bateman, and Music/WeirdAlYankovic as Paul Allen.
* The [[https://www.youtube.com/watch?v=eP9W04ADO_Y Chainsaw]] Scene, especially the part where he drops the chainsaw down a flight of stairs onto her. He actually tries ''tracking'' his target from above by holding the chainsaw out with one arm and circling it around and around. And he hits the target.
* "Their lyrics are as positive and affirmative as anything I've heard in rock. Christy, get down on your knees so Sabrina can see your asshole... Music/PhilCollins' solo career seems to be more commercial and therefore more satisfying, in a narrower way. Especially songs like 'In the Air Tonight' and 'Against All Odds'-- Sabrina, [[https://www.youtube.com/watch?v=XMmlJnxP7Y4 don't just stare at it, eat it]]."
** At the beginning of this scene, when Patrick is blathering on about his favourite music, there's a blink-and-you-miss-it example as the two prostitutes clearly share an irritated "Jesus, can you ''believe'' this asshole?" glance with each other.
* Bateman's [[EyeTake surprised look]] when he shoots at a police car [[MadeOfExplodium and it explodes.]]
* Bateman making ridiculous faces as he flexes his muscles at himself in the mirror, while he's having sex with two prostitutes, as Phil Collins's "Sussudio" plays.
* In the movie, when the hooker is trying to escape from Bateman's apartment, she trips and falls, and Bateman catches up with her... only for him to stop, grab her leg, and start biting on it. She stares at him numbly for a moment, then slowly draws her other leg back and kicks him square in the face. In what ''should'' be a horrifying scene, [[MoodWhiplash the audience laughs their collective asses off]].
** "Not the face! You bitch!"
* After Luis [[MistakenForGay mistakes]] Patrick's attempt to strangle him as an attempt to come on to him, Patrick scrubs his hands furiously in the sink... without taking his gloves off.
** This scene:
--->'''Luis:''' Patrick!\\
'''Patrick: WHAT IS IT?!'''\\
'''Luis:''' Where are you going?\\
'''Patrick:''' [[CharacterCatchphrase I have to return some video tapes]].
** Ten times funnier as Patrick awkwardly leaves, he again hears Luis call him and he turns to see Luis doing a phone gesture and mouthing "I'll call you," which only causes Patrick to leave in embarrassment.
* Thanks to certain similarities between the characters of Patrick Bateman and [[Franchise/{{Batman}} Bruce Wayne]], quite a bit of metahumor is to be had at the casting choice of Christian Bale in ''Film/TheDarkKnightTrilogy'', complete with Youtube mashups of the two characters to create such classics as "[[NinjaPirateZombieRobot The Dark American Psycho Knight]]".
** Or the meta-humor that comes from the guy who played Batman straight up murdering [[Creator/JaredLeto the guy]] who would go on to play ComicBook/TheJoker.
* Patrick's Paul Allen impersonation when he leaves a voicemail on his dead colleague's answering machine.
* "Could you keep it down? I'm trying to do drugs!"
* While on a date with Jean at his apartment, Bateman tries to come up with a plan to kill her and has a smooth escape when she gets curious about what he's playing at.
-->'''Jean:''' What's that?\\
'''Patrick:''' Duct tape. I need it for... [[CaptainObvious taping something.]]
* Patrick tries to book a reservation at Dorsia, with the Dorsia employee unable to stop laughing.
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