!!The Swedish Adaptations:
* CreatorInJoke: ''The Girl Who Played With Fire'' has a scene where EXPO - the magazine Stieg Larsson founded in the 90s - is on display. In the same film, a scene at the police station also has an offscreen voiceover saying "there's a Stieg Larsson here to see you".
* DyeingForYourArt: Noomi Rapace prepared for seven months, taking kick boxing lessons, went on a strict diet and had her eyebrows and nose pierced. She also got her motorcycle licence.
* PlayingAgainstType: [[spoiler:Peter Haber]], cast as [[spoiler: monstrous serial killer and rapist Martin Vanger]], is known mainly for two roles. One being a ByTheBookCop named Martin Beck in twenty-something movies. The other, a role practically everybody born in Sweden during the 80's and early 90's identify him with, is the sweet bumbling Papa Rudolph in the immensly popular "Sune" series. To put it in terms for a more international audience, it's basically like seeing [[Series/MalcolmInTheMiddle Hal]] playing a Complete Monster serial killer (rather than [[Series/BreakingBad a school teacher turned drug lord]]). And doing it superbly!
* RealLifeRelative: In the Swedish film of ''Dragon Tattoo'', Lisbeth's mother Agneta is played by Noomi Rapace's mother, Nina Norén.
* StarMakingRole: Creator/NoomiRapace was mostly a stage actress before being cast in the trilogy, which has brought her international acclaim. It led to high profile roles in ''Film/SherlockHolmesAGameOfShadows'' and Ridley Scott's ''{{Film/Prometheus}}''.
* WhatCouldHaveBeen: Creator/DolphLundgren turned the role of Ronald Niederman down, and Micke Spreitz played it instead.

!!The American Remake:
* ActorAllusion: Composer Allusion - A character in the US version is seen wearing a Music/NineInchNails shirt - while [[PopStarComposer Trent Reznor]] is the co-writer of the score.
* ActorInspiredElement:
** The [[SoundtrackDissonance use of Enya's "Orinoco Flow"]] in the American film was suggested by Daniel Craig. It was initially met with disbelief and doubts with regards to whether or not it would work. The rest, as they say, is history.
** Rooney Mara told David Fincher that Lisbeth Salander was a natural redhead who dyed her hair black. Thus they created a red merkin for her to wear.
* DevelopmentHell: Sequels for the film got stuck in development hell for so long that Sony decided to just skip to ''Film/TheGirlInTheSpidersWeb'' with an entirely new cast.
* DyeingForYourArt:
** According to director Creator/DavidFincher, Creator/RooneyMara dove headfirst into her portrayal of Lisbeth, chopping off her long brown hair to a dyed-black pixie cut, bleaching her eyebrows, getting both ears pierced (all together four times), and getting her eyebrow and one nipple pierced as well (nose and lip piercings were fake). Say what you will about her, she doesn't do things in half measures.
** Daniel Craig also gained weight to make himself look more normal and less like James Bond.
* EnforcedMethodActing: The physicality of shooting the rape scene was so severe that the bruises on Rooney Mara's body in the shower scene were real. Her make-up artist was even fooled into thinking her make-up had already been applied.
* FakeNationality: All over the American film version. The only actual Swede in the main cast is Creator/StellanSkarsgard. The rest are British, American, or Canadian, except for one Dutch man, and one Croatian.
* RemakeCameo: Creator/DavidDencik - who plays the young Morell - had played Janne in the original Swedish film.
* StarMakingRole: Creator/RooneyMara had already been getting lots of attention for her OneSceneWonder role in ''Film/TheSocialNetwork'', but this made sure that everyone knew who she was.
* ThrowItIn:
** Mikael catching the water bottle was an ad-lib by Daniel Craig.
** While filming a diner scene, the crew discovered Creator/MichaelNyqvist's daughter working there while attending school. So they wrote in a couple of lines for her. She plays the barista giving Mikael a sandwich at the beginning.
* WagTheDirector: Mikael having an English accent was because Daniel Craig thought the idea of American, Canadian and British actors using bad fake Swede accents was silly.
* WhatCouldHaveBeen:
** Creator/EmilyBrowning, Creator/EvaGreen,[[note]]Which would have caused a ThoseTwoActors situation considering that only five years prior, she played a [[GirlOfTheWeek Bond Girl]] opposite Creator/DanielCraig as Film/JamesBond in ''Film/{{Casino Royale|2006}}''[[/note]] Creator/AnneHathaway, Creator/ScarlettJohansson, Creator/KeiraKnightley, Creator/JenniferLawrence, Creator/CareyMulligan, Creator/ElliotPage, Creator/NataliePortman, Creator/LeaSeydoux,[[note]] Which would have ''also'' caused a ThoseTwoActors situation as she too would go on to play a Bond Girl opposite Daniel Craig in ''Film/{{Spectre}}''[[/note]] Creator/KristenStewart, Creator/OliviaThirlby, Creator/MiaWasikowska, Creator/EmmaWatson and Creator/EvanRachelWood were among the actresses considered for the role of Lisbeth Salander. Some actresses turned down the role; others were rejected by filmmakers and the studio--Johansson for being "too sexy", Lawrence for being "too tall", etc.
** There was a campaign among fans to get Noomi Rapace to reprise her role in the American remake too. Creator/RogerEbert even championed it. She declined, having had enough of playing Lisbeth for three years in a row.
** Creator/GeorgeClooney, Creator/JohnnyDepp, Creator/ViggoMortensen, and Creator/BradPitt were considered for the role of Mikael Blomkvist. Creator/DanielCraig also turned the role down initially because he wouldn't be able to commit with ''Film/{{Skyfall}}''. However when filming on that was pushed back, he became available and took the role.
** Creator/MaxVonSydow was the original choice to play Henrik, but he had to drop out and was replaced by Creator/ChristopherPlummer.
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