The Social Network has debuted at the top of the US box office.
The David Fincher-directed drama about the founders of Facebook, starring Jesse Eisenberg and Andrew Garfield, was the No 1 weekend film with 23 million dollars.
The movie traces the history of the social networking website from Harvard University, where computer whizz Mark Zuckerberg (Eisenberg) and best friend Eduardo Saverin (Garfield) launched the site, through its meteoric rise with 500 million members and a stock value in the billions.
The film also follows the nasty legal fight as Zuckerberg faces lawsuits by Saverin, who says he was cheated out of millions, and three other students who claim he stole the idea from them.
Justin Timberlake co-stars as Napster founder Sean Parker. Facebook has called the film "fiction" about its founder, the notoriously private Zuckerberg.
The weekend's other new wide releases had weak starts. Case 39, starring Renee Zellweger, opened at No 7 with 5.35 million dollars, while Let Me In, based on the novel Let the Right One In, debuted at No 8 with 5.3 million.
Animated adventure Legend Of The Guardians: The Owls Of Ga'Hoole, held up well, retaining the No 2 spot in its second weekend with 10.9 million and raising its total to 30 million.
The previous weekend's top earner, Wall Street: Money Never Sleeps, slipped to third place with 10.1 million dollars, lifting its total to 35.9 million.