The Director’s Guild Theatre was packed for this evening’s screening of “The Social Network,” the story of Facebook and of Mark Zuckerberg and others whose roles in creating the site are disputed. Elsewhere, Mark Zuckerberg and Lady Gaga were both watching, too, according to Aaron Sorkin, who wrote the script. Sorkin guessed that this had to be “the first time they have done anything together.”

“They went dressed as each other,” said Justin Timberlake, who plays Sean Parker, the co-founder of Napster. “She wore a hoodie and flip flops. And he wore olive…he wore olives.”

For the record, that bit about the olives is not true. And accuracy, Sorkin was eager to point out, does matter to him with this film. He cut off the moderator, The New Yorker’s Nicholas Thompson, mid-question to respond to a line from a story about “The Social Network” in New York magazine:

“I don’t want my fidelity to be to the truth; I want it to be to storytelling,” Sorkin says, blithely tossing potential critics a couple of hundred rounds of free ammo.

“I was referring to one moment in particular,” Sorkin said. And it was a moment meant “to illustrate the point that our fidelity is to the facts.”

The moment: Zuckerberg has just been dumped, and returns to his dorm room, where he goes on to post nasty things on his blog about his ex-girlfriend and to create Facemash, a sort of Harvard-only, head-to-head version of Hot or Not, all while drinking. As Sorkin wrote the scene, Zuckerberg put down a glass, threw in some ice, poured some vodka, then topped it off with orange juice. But before filming began, they learned that, on that night, Zuckerberg had actually been drinking Beck’s beer. Sorkin didn’t think it mattered, but the director, David Fincher, insisted they correct the script. “Come on David, drunk is drunk,” Sorkin said he argued. That, he explained, was the sort of infidelity to the facts he was willing to tolerate: a screwdriver in the place of beer. (In the end, Fincher won; Zuckerberg drank Beck’s.) But Sorkin challenges people to find other inaccuracies. (David Kirkpatrick, author of “The Facebook Effect: The Inside Story of the Company That Is Connecting the World,” gives his run-down of what’s fact and fiction. Jose Antonio Vargas also addressed the film’s fidelity to the truth in his piece on Zuckerberg.)

So while we’re setting the record straight, Zuckerberg didn’t watch the film with Lady Gaga, just perhaps at the same time—but in different places. Zuckerberg reportedly rented a theatre to screen “The Social Network” for the Facebook staff. Afterward, according to an e-mail that Eisenberg received today from his cousin, who is close to Zuckerberg, they all went out for appletinis, which Eisenberg and Timberlake drink at their first meeting in the film. Eisenberg’s cousin says appletinis have been declared the “new official drink of Facebook,” which Eisenberg thinks is proof that the Silicon Valley entrepreneurs and their Hollywood counterparts “have mended fences.”

Photograph: Amy Sussman/Getty Images