It seems that I'm the last in a long line of people to praise this book, and worthy of praise it is. Not only is the story engaging (who doesn't like a good murder-mystery?) and the characters all well rendered and written (I can't think of Picasso in any other way now) but the use of colour is exceptionally striking as the panels adhere to a really structured format throughout.
I love this movement to take early twentieth century figures in Paris and turn them into a sort of League of Extraordinary Gentlemen. This book explores quite a few things at once, which is the essence of the art that Braque and Picasso were striving for. In one story we have the exploration, definition and construction of a new artform, multiple character interaction subplots and a surreal murder mystery. And at its core each element presented in the book is an exploration or reflection of that basic artistic idea presented via Braque and Picasso. To see something from many angles and using colour for emotional resonance allows the art to explore a new type of reality.
The comic itself, the physical object of the book, reflects this as well. The book is a landscape format often used to gather newspaper funnies, but it is vibrantly colourful in a minimalist sense with two colours used per page. And while all this fits into the idea of looking at the form slightly different, Bertozzi also manages to show how all movements that work out a final definition also become constraining in its own way. There is a rigid grid of four panels per page, that doesn't ever change. This can reflect the cubist ideas but it also shows how that movement itself, after its novelty wore off, became restrictive in its own right.
So, you can explore this book on whichever level you like, and I feel that if I had a bit more art history knowledge I'd enjoy it a bit more (or at least be able to place more of the characters easily). On it's purest level, this is a story you can just pick up and enjoy on face value. You don't have to think about the form or the ideas if you don't want to, you can simply read about a bunch of guys doing wild things in order to capture a demon sprung forth from a canvas. It is a rollicking adventure as much as it is a meditation on immortality through art.