Ten minutes to one in the morning, and the iPod was filling the air with a mixture of pop and folk rock through expensive-looking speakers. Eduardo Saverin, his thin slacks hanging over storkish legs, an oxford shirt buttoned up to his throat, was surrounded by four similarly dressed guys. Somewhere, there were two or three girls. Underground frat life at Harvard was a far cry from Animal House.

The party was a meet-and-greet for Alpha Epsilon Pi, a Jewish fraternity. “It’s not that guys like me are generally attracted to Asian girls,” Eduardo was saying, between sips of punch. “It’s that Asian girls are generally attracted to guys like me.” The other kids nodded. They were the kind of geek that elaborated a complex algorithm to try to explain the connection between Jewish guys and Asian girls.

One of them was wearing cargo shorts and sandals with no socks despite the sub-zero weather. There was something playful about his light blue eyes but his narrow face was otherwise devoid of expression. His name was Mark Zuckerberg; he was a computer science major. In high school, he had supposedly been some sort of master hacker — so good at breaking into computer systems that he had ended up on some FBI list somewhere, or so the story went.

Rumour was, Microsoft had offered him more than $1m to work for it and, amazingly, he had turned it down. To Eduardo, the idea that someone would turn down $1m was both fascinating and a little bit appalling. This was someone he wanted to get to know better. Anyone who’d turned down $1m at 17 was probably heading somewhere.

“I have a feeling this is gonna break up in a few minutes,” he said to Mark after the others had wandered off. “If you want, there’s a party on my floor we could check out. It’s gonna suck, but certainly no worse than this.”

Mark shrugged. “Why not? I’ve got a problem set due tomorrow, but I’m better at logarithms drunk than sober.”

Within a few weeks in that late autumn of 2003, they were good friends.

FROM the shore of the George River, the two rowers looked like robots: exact replicas of each other, from their sandy hair to the determination on their matinee-idol faces and the muscles rippling beneath grey Harvard sweatshirts.

Three hours later, Tyler Winklevoss could still feel the river resonating beneath him as he dropped into a chair next to Cameron, his twin brother, who was eating a mountainous breakfast. There were days when it seemed all they did was row, eat and sometimes sleep.

A group of girls kept glancing at him and Cameron. It was something Tyler had grown pretty used to. Hell, they were identical twins. But it was more than that. They had status on campus, and not just from being premier athletes.

They were members of the Porcellian, the most prestigious, most secretive and oldest of Harvard’s eight all-male clubs, which had nurtured generations of world leaders, financial giants and powerbrokers. Tyler and Cameron’s father was immensely wealthy.

The Porc was serious business, which was something Tyler could appreciate. Serious business was why he and his brother were meeting the third kid at their table. Divya Narendra wasn’t an athlete, but the Winklevoss brothers were on a secret project with him.

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