I have never really been a huge fan of historical fiction. Although a lot of it, surprisingly, is written by real historians, it tends not to be very convincing. This however is different. Harriett is a first-class historian her sister Helen is too )and the amount of research she did for the novel really shines through. Not just along historical lines either...she consulted psychoanalysts and in particular the Jungian analyst Matthew Harwood, as well as clothing experts, martial arts gurus,experts on the Italian Wars and anything else you can think of. So the first criterion for an historical novel - that it is believable - is met in spades.
But it is, as other reviwers have said, a real page turner. You just don't want to put it down. The unique view point from which it is written, inside Henry's own head, helps it enormously and gives an immediacy which is brilliant. Breathtaking. And it really does give us an opportunity to re-assess what we think of Henry, and take a different view on him than that provided by the portraits with which we are so familiar...the ogre who thinks nothing of executing wives or friends, or the gross, obese tyrant totally self-centred, vain and dictatorial.
It is without doubt the best book I have read this year, the most exciting, the most thoughtful, and one I would recommend without resrvation to teens or adults. Do read it.