Eighteen months have passed since the events described in The Alchemist of Souls, and Mal Catlyn is now working for Walsingham as a spy at the French court, aided by his "valet" Coby Hendricks. Their current mission is interrupted, however, by a letter telling them to return to London immediately. There has been a rift with the skraylings over the presence of renegade skraylings who have deliberately reincarnated in humans in England. Rumour has it that skrayling vessels have been spotted in the eastern Mediterranean in increasing numbers, fuelling suspicions of dealings with Venice. Mal is instructed to travel to Venice forthwith to find out if these suspicions are true and, if they are, to break up this new alliance by any means necessary...