Our author, Michael Lewis, starts by talking about the absurdity of the "Wall Street investment bank" (p.1). And this dude should know—he worked for Salomon Brothers (a major firm) when he was twenty-four years old.
Lewis actually wrote a book about this experience called Liar's Poker. It eviscerated the industry, calling out his peers for their lack of knowledge and his bosses for their greed.
Instead of exposing the industry as a scam, however, the book seemed to actually encourage more young'uns to join it. Whoops.
In a similar way, the industry as a whole just got shadier and shadier over the years.
Everything changes in 2007, when an obscure analyst named Meredith Whitney makes a big prediction: the bank Citigroup is in rough shape and will need to "slash its dividend or go bust" (p.9).
Four days later, that's exactly what happens. This lady is Nostradamus.
Whitney's not done yet, either. Now that the world's eyes are on her, she tells Wall Street that its wrong-headed investments in the subprime mortgage bond market (more on that later) will have huge consequences.
Spoiler: Whitney's completely right. And she isn't the only one: some guy named John Paulson makes almost $25 billion betting against the subprime mortgage market.
One day, Lewis visits Whitney and asks her how many people knew about this subprime disaster before it happened. She gives him a list that has John Paulson smack dab in the middle.
At the top, however, is Whitney's former boss and mentor, Steve Eisman.