Well, I enjoyed the show last night very much indeed, but I have to tell you that it just picked up the barest smidgens from the book. It did not follow the book properly AT ALL! Very, very different story!
The book is fantastic, but I figure it would take a minimum of SIX hours of film to do it credit and give you all of the nuances of the plot. For one thing, in the book the prince dies in The Vatican, falling (being sent, actually) down from the cupola of St. Peter's. For another, the girl who plays the prostitute in this film is not one at all, but a mad woman who is second cousin to the murdered prince and who remains a prisoner in her home, where she dresses her dolls all day, every day. Her brother makes an incredible name as a fashion designer, but all of the designs are HERS. She does not know this. He is the one plotting and having a hand in the death of the prince and the other plotters. He is also a cross dresser, so he is seen at certain places in the book as a woman. Dibdin's descriptions of Rome and of The Vatican State are exquisite and very interesting. Also the relationships of the various departments and agencies. I love the Italians, but am happy not to be one, as there is no such thing as a direct way to get things done there.