Greenberg follows a group of researchers and law enforcement through some of the more notable investigations of cryptocurrency-funded crime. Bitcoin's blockchain was once widely believed to be untraceable, hence its widespread adoption by the criminal underworld. It wasn't, and this is the story of how that belief backfired.

I've removed one star due to some of the limitations of the technical explanations. There's always a fine line to walk between providing so much detail it loses readers versus providing just enough so that non-technical people get the gist of what's happening, and I don't feel that Greenberg walked that line particularly well here. What Bitcoin's blockchain is and how it works just isn't explained well enough given it's the central character in the story.

Otherwise, Greenberg does an excellent job revealing the mystery and provides a great look at some of the darker parts of the Internet.