For those who have seen the movie based on this book, I still think it is in your best interests to read the book. It's fascinating, to put it mildly. This isn't exactly a story where I can ruin the ending: the big investment banks created derivative products called CDOs based on subprime (meaning unlikely to be paid back) mortgages. The CDOs were insured (mostly by AIG) by Credit Default Swaps, and AIG and others happily allowed people without any investment in CDOs to buy Credit Default Swaps on their own (basically allowing the creation of a derivative of a derivative, the synthetic CDO). The financial rating institutions, like Moody's and Standard and Poor's, rated these CDOs as AAA, which meant that insurance companies and retirement funds could invest in them. (As a note: AAA means as safe as a government bond, and therefore, riskless). This was a catastrophe waiting to happen and it appears that the banks really had no idea what they were doing, despite being warned by at least a few people. While this all sounds very technical, Lewis manages to make it entirely understandable.

This is essentially a story about what happens when we let our financial institutions run amok through deregulation. Deregulation began with Reagan, and then continued onwards through the Bush Sr, Clinton, Bush Jr., and Obama administrations (I can only imagine it will continue through the Trump administration as well). This book is a perfect story of a perfect storm, and if it is missing anything, it is a call to action. But I think the call to action is implied by the very nature of the events Lewis describes.