TIME TRAVEL. ALTERNATE HISTORY.
Yes, I am shouting. Because I didn't realize from the blurb that this wasn't a fairly straightforward "What happened to the princes in the Tower" book. The story is not that historian Roger Ward travels back in time to find the truth. It is that his adventures cause major changes in the timeline so that the world he came from may never exist.
The story bounces between the 21st and the 15th centuries, and between the history that we know and the history as it would be if the events in the book had happened. When Margaret Beaufort, mother of King Henry VII (the first Tudor king of England) learns how to travel forward in time to the 20th/21st century her actions change history. When a 21st century history professor travels back to the 15th century his actions also change history.
Despite the characters' understanding that their actions would have an impact on history, they continued to believe that the dates of death in the chronicles that they read wouldn't change. For example, Henry VII might be deposed by the Yorkists but he would still live to the same time as he would have if he stayed on the throne. This made no sense to me.
I kept wanting to throw this book at a wall, but since I was using an e-reader I couldn't do that.
Rating 1.5 because I actually was interested enough to finish it, even though I kept wanting to yell about how stupid it was.