Morris does a nice job summarizing some of their key accomplishments. While doing that, the reader will learn about some important events in the past forty years or so. The book is divided into four chapters. One chapter is dedicated to each sage and the final chapter is some of the author's thoughts and insights on capitalism and the markets. He interviewed Soros and Volcker but did not have direct access to Buffett.
This is not a light read. Like his previous book, "Trillion Dollar Meltdown", background knowledge of finance and economics makes the reader appreciate the book more. The casual reader who wants to learn about these three important figures may get confused at some of the more intricate financial parts of the book. I greatly respect the three sages but I disagree with the author that the three saw the 2008 crisis coming. While they might have known that we were on a path of destruction, even they did not know how and when it would manifest itself in the real world. If they did, you can be sure that Soros and Buffett would have made billions more than they did at that time.
Soros has written many books. Morris summarizes Soros' philosophies on philanthropy and investing. Large section is dedicated to recounting Soros' one year diary in the 1980's. Unlike, Buffett, Soros' investing strategies are mysterious. Aside from very general theories and thoughts, Soros has not described how he goes about making investing decisions. Soros' son even acknowledges that his father's back pain may influence his investing decisions more than anything else. I am skeptical of his son's anecdote (which Soros, himself, does not deny) given Soros' amazing success.
I have read extensively on Buffett so I got very little out of that chapter, but if you know little about Buffett, then you may find it worthwhile. This chapter is based on what has already been written about Buffett and his own letters to Berkshire Hathaway shareholders. If you have read Schroeder's "Snowball", then perhaps you, too will find little new in this section.
I got the most out of the Volcker section mostly because I knew least about him. Morris' account of how Volcker managed to break inflation was interesting. He takes you behind the scenes of the Fed at the time.