Arthur C. Clarke winner and Sunday Times bestseller returns to a world steeped in magic - and the Tyrant Philosophers' campaign to bring reason, logic and 'perfection' to it.

As the Palleseen's campaign to bring Perfection and Correctness to an imperfect world rages on, Eres Ffenegh - "the City on the Back of a Crab" - is the next state slated for conquest. But its citizens won't give up sovereignty easily.

The siege has dragged into winter and the defenders - both locals and Pal renegades - hold an uneasy alliance against the enemy at the gates, while the Pal army is looking over its shoulder for the next self-destructive dictate of their government back home.

Within the city, Devil Jack, a good man apprenticed to the notorious conjurer known as the Widow, is driven to bargaining with hell to get back what he's lost. Meanwhile Kiffel ea Leachan is the city's champion, a child of privilege who's just lost everything to the invaders. Both must try to survive the siege and make their own destinies in a world that's cut them loose.