LET'S leave aside the social problem of Facebook as a privacy violator. I'm not up to the depths of tireless radio investigator Dave Emory, who reached for his Foucault when titling a recent communiqué "In Your Facebook: A Virtual Panopticon?" The real-life Mark Zuckerberg couldn't possibly be as chilly as his namesake, the antagonist of David Fincher's The Social Network.

This is a fiendishly clever and funny movie about the creation of an Internet monster. The cry "The site's alive!" is certainly meant to echo Dr. Frankenstein's shout when he first saw his creature twitch. As Facebook founder Mark Zuckerberg, Jesse Eisenberg gives a master class on recessive acting: he's beady-eyed and covert, with the occasional pit-viper-like sway of a truculent, lowered forehead. People who saw Eisenberg in The Squid and the Whale know how bravely he stripped out what's called "youthful idealism" from his lead role. Eisenberg amplifies the quality he showed us then, without distorting it at all. His Zuckerberg embodies the kind of remorseless superiority that always looks comically childish and wounded. He becomes the kind of CEO who thinks that it's killing wit to put an obscenity on his calling card.

Director Fincher makes this story of betrayal glide along, between the narrows of beautifully balanced flashbacks. The film shuttles between the present-day deposition of the now arrogantly rich Zuckerberg, being sued by a quartet of burned partners (among them his former best friend Eduardo, played by Andrew Garfield).

Facebook has its origins in the dorms of Harvard in 2003. The young Mark decides, one drunken night, to get revenge on a girl who spurned him. First, he denounces the smallness of her tits on his blog; then he hacks into the computer "facebooks" of the various houses at the university to create an online game of rate-the-hotties. The hacking gets him suspended for six months. The incident attracts the interest of a pair wealthy twin WASPs called the Winklevosses (played by a digitally duplicated Armie Hammer), who want to finance a new kind of social networking tool.

Zuckerberg devises Facebook as we know it: as a way to tell of singleness or availability, to distribute trivia and chat with friends. Fincher works very creatively around the visual problem of a showing a solitary man tapping at the computer. This means an extravagant (if extraneous) passage about a sculling competition in England, marvelously made to look like an antique table-top model come to life.

The mole-person Mark forecasts a scary future: "We lived on farms, and we've lived in cities, and now we're going to live online!" This prediction comes before he learns a more pleasant use of power. He meets the founder of Napster, Sean Parker, played by Justin Timberlake as a happy wastrel. Parker lures Zuckerberg West into everything California represents: girls, drugs, drinking margaritas out of pint beer glasses and ziplining from a roof into a swimming pool.

The Trent Reznor and Atticus Ross music seems more like the sinister David Byrne and Eno we loved than the flowery, love-struck Byrne and Eno in Wall Street: Money Never Sleeps. The music is turned up for the scene when evil goes mega; the camera makes its own zipline ride through a Ruby Skyeish San Francisco nightclub to zero in on Parker's face, flashing every diabolical color from the club's lights. This is one mere touch of the taste and intelligence of Fincher regular cinematographer Jeff Cronenweth, who keeps us oriented by making the walnut-lined tombs of Harvard so different from the lambency of the sun in Palo Alto.

The film is almost an all-male world, though some small room has been made for women: Rashida Jones is the moral center, a voir dire expert at the legal firm deposing Zuckerberg.

Aaron Sorkin's wild, witty script hands out some punishment that goes beyond the financial: this Zuckerberg, like Jay Gatsby and Charles F. Kane, is cut off from what he most wanted in life. But The Social Network, a comedy in the Balzac sense, is a balancing act; the mockery and disgust of greed matches the essential lightness of the situation. It's only Facebook, after all.

THE SOCIAL NETWORK

(PG-13; 120 min.), directed by David Fincher and starring Jesse Eisenberg, plays countywide.

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