The foundation of online phenomenon Facebook comes in for scrutiny in this fact-based drama, which turns the site's formative years into a morality tale for our times. Computer-science student Mark Zuckerberg (Jesse Eisenberg, giving a subtly commanding performance) is an unloved outsider at Harvard in 2003, but finds a way of circumventing the university's traditional elite by creating the networking technology that eventually makes him one of the world's youngest billionaires. Along the way, there's camaraderie, betrayal, class tension and much litigation: both his one-time best pal Eduardo Saverin (Andrew Garfield, providing the conscience of the piece) and super-snooty rivals the Winklevoss twins (Armie Hammer, in a dual role) sue for their slice of an increasingly large pie. The dazzling wordplay from screenwriter Aaron Sorkin (TV's The West Wing) and David Fincher's intensely focused direction work in concert to favour character conflict over computer geekery, digging deep to elucidate the story's essential tensions between greed and loyalty, and online and real-world friendship. It's riveting stuff, not least when Justin Timberlake swaggers on as cocksure internet visionary Sean "Napster" Parker. Most significant though, is how this brilliantly assembled cautionary tale gets straight to the heart of the human needs and failings underpinning dizzying technological advancement, creating one of the truly defining films of its era.

In 2003, Harvard undergrad and computer programmer Mark Zuckerberg begins work on a new concept that eventually turns into the global social network known as Facebook. Six years later, Mark is one of the youngest billionaires ever, but his unprecedented success leads to both personal and legal complications when he ends up on the receiving end of two lawsuits, one involving his former friend.