Turn-of-the-century Paris was the beating heart of a rapidly changing world. Painters, scientists, revolutionaries, poets -- all were there. But so, too, were the shadows: Paris was a violent, criminal place, its sinister alleyways the haunts of Apache gangsters and its cafes the gathering places of murderous anarchists. In 1911, it fell victim to perhaps the greatest theft of all time -- the taking of the Mona Lisa from the Louvre. Immediately,...