* ActingInTheDark: Penn Badgley didn't know that [[spoiler: Dan was actually Gossip Girl]] until right before the scene was to be shot.
* ActorAllusion:
** Blair referring to Georgina, played by [[Series/BuffyTheVampireSlayer Michelle Trachtenberg]], as a vampire.
** Chuck, played by Londoner Ed Westwick, gets his haircuts at Piccadilly.
** Blair compares Chuck to House. Leighton Meester guest-starred on ''Series/{{House}}'', playing a teenager with a huge crush on the title character. Coincidentally, Chuck and House are both dark, twisted JerkWithAHeartOfGold type characters, and Ed Westwick and Hugh Laurie are both Englishmen while their characters are American. What makes it funnier is the scene where Chuck is talking to Blair about her British boyfriend and says: "''You can't tell me Bertie Wooster is satisfying your needs''."
** Blair mentions herself and Chuck role-playing "''Literature/WutheringHeights''". Ed Westwick had been cast to play Heathcliff in a new remake but was dropped not long before the episode where Blair makes the mentioning aired.
** As a side effect of the show's IdiosyncraticEpisodeNaming, season four's "The Townie" references ''Film/TheTown'' in which Blake Lively has a role. The same season also saw "Panic Roommate" mash up ''Film/PanicRoom'' and ''Film/TheRoommate'' (Leighton Meester plays the title role in the latter), and "Easy J" riff on ''Film/EasyA'' (in which Penn Badgley appears). The first season also has an episode called "Blair Waldorf Must Pie!" (from ''Film/JohnTuckerMustDie'', which also has Penn Badgley) and the SeriesFinale is called "New York, I Love You XOXO" (after ''New York, I Love You'', with Blake Lively[[note]] and Rachel Bilson, who has an uncredited cameo in the episode[[/note]]).
** In Season 1 when Jenny is trying on dresses at Blair's house, Blair tells her a dress is too HannahMontana. Creator/TaylorMomsen was one of many actresses considered for the role.
** During the build up to and actual [[spoiler: Blair's wedding]], Wallace Shawn makes at least two ''[[Film/ThePrincessBride Princess Bride]]'' references by name.
** In Season 6, Chuck tells Nate that maybe he needs to find himself a ''Film/HotTubTimeMachine''. Former guest star Sebastian Stan (Carter Baizen) starred in this movie.
** In the final season's "It's Really Complicated," when Serena tells Blair that her ex Steven (played by Barry Watson) tried to get back with her, Blair (who'd rather it was him than Dan again) replies "Ooh, you must be in [[Series/SeventhHeaven seventh heaven]]!"
** Blair has spent time in [[MonteCarlo Monaco]] before.
* ActorSharedBackground: Blake Lively has a brother called Eric, just like her character Serena.
* ApprovalOfGod: Cecily von Ziegesar, author of the original books, liked all the representations of her characters. The exception is Vanessa - who is a bald Goth in the books and gets AdaptationalAttractiveness to be played by the very pretty Jessica Szohr in the TV show.
* CreatorBacklash:
** Blake Lively later called it "emotionally compromising" to play Serena, and hated filming all the sex scenes.
** Chace Crawford didn't enjoy his time on the show either and was glad when it finally ended.
** Penn Badgley didn't take too kindly to TheReveal that [[spoiler: Dan was actually Gossip Girl all along]], finding it as much of an AssPull as fans did.
* DawsonCasting:
** All the main "teen" cast, with the exception of Jenny apply into this trope. Particularly notorious is Nicole Fiscella (Isabel Coates, one of the mean girls), who was born in ''1979''.
** An example for season 6 is Sage who is 17 played by [[Series/{{Skins}} Sofia Black D'elia]] who was born in 1991, two calendar years older than Momsen.
** Defied to an extent by Kristen Bell. She was interested in the project after ''Series/VeronicaMars'' wrapped, but realised she was too old at twenty six to convincingly play one of the teens. So as a compromise, she provided the voice of the eponymous Gossip Girl.
* DyeingForYourArt: Leighton Meester dyed her blonde hair brown before her audition, and kept it brown whenever the show was filming.
* EnforcedMethodActing: Billy Baldwin refused to meet Blake Lively before their first scene together because he wanted the experience of seeing your father/daughter again after 14 years to be as real for both of them as possible. He also stated that he pretended Blake was his real life daughter.
* FakeAmerican: Chuck Bass is played by English Ed Westwick.
* FakeBrit: Lord Marcus, played by American Patrick Heusinger. Making it an American playing a Brit who fakes being American. Add to that the scene where Chuck (played by a Brit, as noted above) imitates Marcus' accent to pull a BedTrick on Blair. A Brit playing an American faking a British accent as done by an American.
* IAmNotSpock:
** Leighton Meester appears to have fallen headlong into it. Despite well-received performances in several films, most of her mainstream work flopped, and audiences weren't able to see her anyone besides Blair Waldorf.
** Blake Lively meanwhile has done her hardest to avoid this - including taking a drastically against-type role in ''Film/TheTown'', and another in ''Film/TheAgeOfAdaline''. Both won her critical acclaim, so it seems to be working.
* {{Jossed}}: Rumours that Jenny was going to have a spin-off when she was PutOnABus were put to rest when Taylor Momsen claimed she wished to pursue her music career in Music/ThePrettyReckless.
* McLeaned: Bart Bass.
* MeanCharacterNiceActor: Leighton Meester is by all accounts a lot nicer than her AlphaBitch character.
* NamesTheSame: Nate Archibald is also the name of a former NBA player.
* TheOtherDarrin: Florencia Lozano plays Eleanor Waldorf in the pilot. Margaret Colin replaces her for the remainder of the show.
* PlayingAgainstType: Michelle Trachtenberg got fame for playing various Woobies or {{Plucky Girl}}s. Playing a ManipulativeBitch like Georgina is very different for her.
* TheRedStapler:
** Chuck's trademark scarf sold out within days of the pilot episode airing.
** A more general example is that there was a ''Gossip Girl'' inspired clothing line produced, of cheaper versions of the designer labels the characters wore.
* RomanceOnTheSet: Blake Lively (Serena) and Penn Badgley (Dan), Ed Westwick (Chuck) and Jessica Szohr (Vanessa) and Leighton Meester (Blair) and Sebastian Stan (Carter). All have now broken up. Matthew Settle (Rufus) and Kelly Rutherford (Lily) also dated in real life.
* ScrewedByTheNetwork: The ''Valley Girls'' spinoff was picked up, but then cancelled before it could even air.
* StarMakingRole: This made Blake Lively a household name.
* StillbornFranchise: 2008 saw the release of ''OMFGG Original Music Featured on Gossip Girl No. 1.'' There would not be a No. 2 (the CD didn't even include the show's opening/closing music for some reason).
* ThrowItIn:
** This ad-libbed dialogue in the last scene from season two:
-->'''Blair''': (''after Chuck told her he loves her'') But, can you say it twice? No I'm serious, say it twice.
-->'''Chuck''': I love you. I love you. That's three. Here's four - I love you.
** The first season received numerous complaints from the Parents' Television Council for being "mind-blowingly inappropriate" and "every parent's nightmare". The show ended up using those as taglines.
* WhatCouldHaveBeen:
** The concept was first pitched as a feature film with Lindsay Lohan as Blair and Justin Chatwin as Nate. Plans fell through, and the decision was made to pitch it as a TV series instead.
** Mischa Barton was approached to play Georgina Sparks even after [[Series/TheOC the last time she worked with Josh Schwartz]], but she turned them down. Enter Michelle Trachtenberg.
** Nate and Jenny's relationship wasn't supposed to end so suddenly, but Chace Crawford was uncomfortable regularly making out with a teenager and supposedly asked for it to be ended.
** A spin-off set in the 80s and revolving around a younger Lily was planned, but the CW passed on the idea. The pilot was later aired during the second season.
* WordOfGod: Josh Schwartz and Stephanie Savage have cruelly crushed hopes for [[FanPreferredCouple Vanessa/Rufus]], saying that fans who want them are barking up the wrong tree.
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