The clockwork kingdom of Saxonia engineered itself into a machine of the law, refashioning even its citizens' bodies into cogs and pistons. Before the chirurgeons and engineers splice his brain inside the crown, Prince Hollownot escapes into the kingdom's flogistan soul, where he sees all possible futures. In one, Princess Sapsorrow can break the law with contradiction and shatter the kingdom. But saving the world from the machine comes at a high price: Her love, her family, and her physical body will all be destroyed. The neighboring kingdom of Bavaria has seen nothing come past the great clockwork wall of Saxonia for centuries until a Straggletaggle appears with an odd physiognomy — maybe human, maybe not — and an incredible tale of escape from Saxonia. She claims ignorance of the nearby fatal airship crash and the exquisite prosthetic foot in the wreckage. When a phonograph wrapped in the shell of a man arrives demanding Princess Sapsorrow's return, Bavaria's disgraced prince and scientist princess, with their intrepid bodyguard, embark on a perilous mission with the Straggletaggle as their guide, to stop a war that, should it start, can only end with Saxonia turning the people of Bavaria into components of its horrific machine.
