Casanova Quinn is an arch-criminal. His father is the world's top cop, running an organization that makes U.N.C.L.E. look puny, and his sister is the top agent for that organization. Casanova, though, prefers being a criminal, just because...and the story takes the reader on a very wild ride into other worlds and various states of being, three headed evil geniuses, robot girls, and a lot of other oddities.
This book was well written and interesting, but I grew tired of the character before the end of the story. Part of the difficulty was the idea that most of the story took place in an "alternate reality" compared to the original character, which meant that neither the reader nor the character had any clue about the rules of the world. In addition, it seemed like a strange parody of all of those "good organization vs. bad organization" spy stories, from the 1960s to now, from James Bond to Nick Fury. By the end, it was hard for me to care who won.
Also, I don't really care for Gabriel Ba's artwork, but that is a matter of taste. Some people like him.