One of the biggest questions of the financial crisis has not been answered until now: What happened at Lehman Brothers and why was it allowed to fail, with aftershocks that rocked the global economy? In this news-making, often astonishing book, a former Lehman Brothers Vice President gives us the straight answers—right from the belly of the beast. In A Colossal Failure of Common Sense   We get a close-up view of the participants in the Lehman collapse, especially those who saw it coming with a helpless, angry certainty. We meet the Brahmins at the top, whose reckless, pedal-to-the-floor addiction to growth finally demolished the nation’ s oldest investment bank. The Wall Street we encounter here is a ruthless place, where brilliance, arrogance, ambition, greed, capacity for relentless toil, and other human traits combine in a potent mix that sometimes fuels prosperity but occasionally destroys it.   The full significance of the dissolution of Lehman Brothers remains to be measured. But this much is certain: it was a devastating blow to America’s—and the world’s—financial system. And it need not have happened. This is the story of why it did.