In 2009, Ben Mezrich’s non-fiction book The Accidental Billionaires: The Founding of Facebook, a Tale of Sex, Money, Genius, and Betrayal was published. It went on to be a huge seller, and studios were interested before it was even released. 2/62

Mezrich’s Bringing Down the House: Six Students Who Took Vegas for Millions had previously been adapted into 21 by Trigger Street Productions, Michael De Luca Productions, Relativity Media, and Columbia Pictures, and they snapped up The Accidental Billionaires too. 3/62

Relativity had just produced Mike Nichols’ Charlie Wilson’s War and took the new project to the war-comedy’s screenwriter, Aaron Sorkin. He said “This is like Shskespeare!” and signed up to write immediately. 4/62

When Sorkin finished the script, Columbia wanted him to direct, even though he’d not directed a film before. He wanted David Fincher and said “let’s send it to him - if he passes, I’ll do it”. Fincher read the script and after 5 pages emailed Sorkin saying “I’m in.” 5/62

When Fincher first met with Columbia he told them he needed a $40m budget to make the film. They said “How about 25?” and he said “No, 40m”. They said “35?” And Fincher said “This isn't a negotiation. That's how much it costs.” and they gave him $40m. 6/62

The lead is Facebook Founder and CEO, Mark Zuckerberg. Reportedly, the first person approached was Shia LeBoeuf, but he said no. Instead, Fincher went through the standard process and had auditionees read from a script of TV hit The West Wing - which Sorkin also wrote. 7/62

Fincher wanted Jesse Eisenberg to audition for Mark but he said no as he didn’t want to read from The West Wing. Fincher had a few pages of The Social Network script sent to Eisenberg and, after he recorded a video audition with his sister. Hallie, Eisenberg was cast. 8/62

Eisenberg has been diagnosed with OCD and said one of the hardest things about playing Mark was having to behave in a way he’d tried not to his whole life. He got every interview he could find of the real Zuckerberg, and listened to them constantly on headphones. 9/62

Eisenberg also read Mark Zuckerberg’s real college application, where Zuckerberg had written about how he loved fencing. So Eisenberg did a couple of lessons before filming. 10/62

Eisenberg added to the script, too. He brought in the notepad that Mark scribbles on during the depositions, and it was his idea for Mark to stand back and film the ziplining scene rather than join in, as he did in the script. 11/62

The second lead is Mark’s best pal and co-Facebook Founder, Eduardo Saverin. Andrew Garfield was asked to audition as Mark but when Fincher saw him, he said Garfield was an actor who wore his heart on his sleeve - and asked him to try out for Eduardo Saverin instead. 12/62

Garfield turned up for rehearsals with a copy of Economics for Dummies as he was trying to get into the head of Eduardo, an economics major. Eisenberg then came in with C++ for Dummies. They both said they only read the introductions then never touched them again. 13/62

Mark’s nemeses in the film are Cameron and Tyler Winklevoss, twins who sue Mark for stealing their idea. Fincher wanted to cast twins but, when he couldn’t find anybody suitable, hired two actors who had similar looks - Armie Hammer and Josh Pence. 14/62

Fincher had just worked with Lola Visual Effects on The Curious Case of Benjamin Button and they recommended using face projection to create the twins: Pence would act the scenes alongside Hammer and Lola would digitally add Hammer’s face over Pence’s 15/62

Pence learned Hammer’s mannerisms, wore motion capture markers on his face and scenes were shot using motion controlled cameras, so each take was identical. Fincher would then choose what take he wanted in the edit. 16/62

Pence said that when he found out his face wouldn’t be seen he threw up and started crying. He does show up in a small role though – he plays the student who Eduardo and Mark stop entering the student bar bathroom when Christy and Alice are in there. 17/62

Hammer and Pence took up rowing for real to prepare for the film and Hammer said it was the hardest thing he’s ever had to do. He had to eat lots of junk food during the shoot so he could keep his weight up. 18/62

The third major character is Napster founder Sean Parker. Jonathan Groff from Glee was considered by Fincher, and apparently the studio wanted Jonah Hill, but Fincher wasn’t keen. Instead, after auditions, former NSync member Justin Timberlake was cast. 19/62

Timberlake was a bit bigger and older than the real Sean Parker so lost about 15 pounds for the role. He ran into the real Parker before filming and said he’d like to get to know him a bit. Parker told him, “Don’t bother. The guy you’re playing is nothing like me.” 20/62

Eduardo’s girlfriend, Christy, is played by Brenda Song. She was mostly known for working on the Disney Channel and said that Disney told her she couldn’t accept the role of Christy because of the bathroom sex scene. She accepted the part anyway. 21/62

Real-life Facebook Founder Dustin Moskovitz is also in the film as a secondary character. He’s played by Joseph Mazzello, maybe better known for playing Timmy, the dinosaur-obsessed young boy in Jurassic Park. 22/62

Aaron Sorkin has a cameo as the executive who meets Mark and Eduardo to talk about advertising on Facebook. He’d had cameos in his own films before but this one wasn’t his idea. Sorkin said Fincher was insistent that he play that part. 23/62

Sorkin’s first draft of was 178 pages, and the studio told him to cut at least 30. He got it down to 162 and when Fincher came in, he said to leave it as it was and he’d have the film still come in at 2 hours. He did that by directing the actors to talk very quickly. 24/62

Natalie Portman was at Harvard between 1999 and 2003 studying psychology and when she found out Sorkin was writing a script about Facebook, she threw a dinner party and invited him so she could give him lots of insider info on Harvard. 25/62

Portman is also the person Divya Narendra is referring to when he mentions a movie star going to Harvard during a deposition. This was clarified in the script at one point, but Fincher wanted to keep it mysterious. 26/62

When Fincher came on as director, the script was sent to Facebook get their blessing. The film’s producer, Scott Rudin, met with Facebook and was told the movie couldn’t be set at Harvard, and they couldn’t call the company Facebook. Fincher decided to do it anyway. 27/62

Sorkin changed a lot of aspects of the book. For example, the story about Eduardo keeping a chicken as initiation into the Phoenix club didn’t happen. The Harvard Crimson did publish an article about chicken torture and the club, but it had nothing to do with Saverin. 28/62

In the film, Mark cuts Eduardo out of the company by creating new shares to dilute his overall ownership. This is how it really happened but, in reality, Eduardo’s shares were reduced to 10%, not 0.03%. 29/62

Some elements that were true: Mark really did drop out of Harvard to move to California and work on Facebook. Eduardo did freeze the Facebook bank accounts. And the real Zuckerberg had a business card that said “I’m CEO, b*tch.” 30/62

The Director of Photography was Jeff Cronenweth. This was his fifth feature as DP, and second collaboration with Fincher, having shot Fight Club as well. Fincher said there was no setup that took longer than 20 mins, and this was the first film he shot entirely on digital. 31/62