The Opening Duet which goes a back and forth

aron Sorkin’s screenplay for the Facebook origin story The Social Network is a dizzying whirl of snappy, fast-paced dialogue; there were few films this year as enraptured with the sound of smart people talking fast. Director David Fincher sets up the picture’s sharp-tongued wit immediately, with a memorable opening scene that finds protagonist Mark Zuckerberg (Jesse Eisenberg), a smug Harvard sophomore obsessed with penetrating the university’s social hierarchy, out at a bar with his girlfriend Erica (Rooney Mara). They volley their dialogue back and forth, the conversation a convoluted series of sidebars, asides, and footnotes, one often charging past the next while the other sputters and lunges. “Sometimes you say two things at once, I’m not sure which one I’m supposed to be aiming at,” she says, not unreasonably, but she turns out to be the slipperier opponent; she breaks up with him at the end of the scene, before he’s even aware of what’s going on. From the standpoint of pure entertainment, the scene is a humdinger — a whiz-bang Sorkin special. But it also sets up the film beautifully, establishing the contradictions of Zuckerberg’s character, the tone and pace of the picture, and the fierce, sexy intelligence of Erica, who becomes the “Rosebud” to Zuckerberg’s Charles Foster Kane.