Sebastiao Raposa was rescued from Lisbon as a teenager, the only one of his New Christian family to escape the Inquisition. In England he was taken in by Benjamin Weaver and trained as his apprentice. Ten years later, he returns to Lisbon with the goal of killing the Inquisitor who killed his parents. But new revelations about how his parents were arrested and attempts to repay those who helped to save him make his mission more complicated than he first thought, and after so many years and with so much unknown, his friends and enemies may not be whom he thinks.
This may be my favorite of David Liss's books yet, although there are some I may need to reread in order to make that determination for sure. It is loosely connected to the Benjamin Weaver series (set some years after his most recent previous appearance, Weaver makes a couple of brief cameo appearances), and reads like a cross between it and The Count of Monte Cristo.
I'd still like to know more about Weaver's life in between the end of The Devil's Company and the beginning of this book, but until that happens, I'll be happy with spinoffs like this.