Meriwether & Co. truly believed that their finely tuned computer models had tamed the genie of risk, and would allow them to bet on the future with near mathematical certainty. Thanks to their cast - which included a pair of future Nobel Prize winners - investors believed them. Four years later, when a default in Russia set off a global storm that Long-Term's models hadn't anticipated, its supposedly safe portfolios imploded. In five weeks, the professors went from mega-rich geniuses to discredited failures. The firm's staggering $100 billion balance sheet threatened to drag down markets around the world. At the eleventh hour, fearing that the financial system of the world was in peril, the Federal Reserve hastily summoned Wall Street's leading banks to underwrite a bailout.