Robert Cecil, Secretary of State to James I, has a problem. He owes a vast and secret debt to the Prince of La Spada, who is dying and has called in the loan and Cecil cannot pay. Even worse, he has staked as security, without royal authority, the King's Great Pearl. To Cecil's surprise, the Prince will agree to a hostage but he wants Cecil's firemaster: Francis Quoynt, the best in his dangerous business. Cecil immediately seizes the chance, for Quoynt also serves as his spy.
La Spada is a wealthy, beautiful Italian citystate the gateway of Europe. Whoever controls the mountain passes of La Spada also controls the flow of intelligence and much of the trade from the Middle East. As his mind disintegrates into fantastic obsessions, the Prince makes his treacherous illegitimate son his heir. Which thwarts the deadly ambition of his daughter, Sofia the Principessa.
Sofia is young, seductive, wily and recently widowed. Already a blooded player of politics, she could outdo Lucretia Borgia in the lethal game of survival. Which she must now play to save herself and her beloved state. As unpredictable as gunpowder, will she choose to seek Francis's heart, or his life? Or both?
Events in The Principessa start two years after those in The Firemaster's Mistress. In the intervening two years, Cecil has fulfilled his promises by being Frances Quoynt's sponsor, and as a result Frances has been the fireworks master of choice of the rich and famous of England. For all of his newly acquired wealth, Frances is somewhat dissatisfied with his life, and he knows that the day will come when the wily Cecil is going to call on Frances to once again undertake some deed for him. When the time does come, he is somewhat surprised to find that it means that he will have to travel to the distant principality of La Spada. The principality is at a critical crossroads in it's history. It's ruler is dying, and there are two possible successor - one is his legitimised son and prescribed heir Ettore, and the other his legitimate daughter Sofia.
As always when working for Cecil, nothing is as straight forward as it seems, because not only is Frances being asked to get lavish funerary fireworks ready and acquire the secret loan bond that could very well be the end of Cecil if anyone in England finds out about it. The Prince is also determined that, in order to ensure that he gets to heaven after a lifetime of debauchery, he must be made to fly towards heaven right at the moment of his death and that Frances is going to help him achieve this goal. The prince is dying of the pox and is completely mad, to the point of killing his attendants for the smallest of reasons. So not only does Frances have to survive the Prince by some how ensuring that he is attempting to do his will, but he has to survive the political manoeverings of the court at this time of change, and that means walking a fine line between Prince Ettore and the Principessa, Sofia. Adding to the complications, there is a smouldering attraction between Frances and Sofia - one that can go nowhere given that Frances is a common firemaster and she is royalty.
Whilst this is once again a very entertaining story, I do think that it lost something in moving away from actual historical events and moving towards fictional places and people. I did check and I could no reference to any place called La Spada, that was supposed to be at a crucial location in Europe - a multicultural crossroads located between the lands of the Hapsburgs, the Italian principalities like Venice, and the Ottoman empire.
One interesting group of people included in the novel were the Uskok's who were the loyal guard of the dying Prince, and who seem to be from a group of Balkan people that I haven't actually heard much about previously.
As a character, Frances was once again well written - a man driven by honour and learning, trying to do the best that he can in difficult circumstances. His relationship with Sofia was complex and twisting. He was constantly aware of the shifting sands in their relationship - never quite sure of whether she was using him or if she loved him. The resolution of their relationship was very surprising to me as it is not one that I could see Frances accepting, but I don't want to say too much more without spoiling!
Sofia was harder for me to warm up to. She was extremely ambitious, and I can see how living constantly in fear of her life would cause her to become as withdrawn and secretive as she was. She did open up to Frances eventually, but she was definitely using him for her own means for a long time. There were glimpse of a kind heart, especially in the way she treated the librarian of the castello, but it probably wouldn't have hurt to see a little more of that side of her.
The story was entertaining, if somewhat fantastical in parts, and is an interesting follow up to The Firemaster's Mistress.