Entertaining if rather anachronistic adventure novel about a clerk who worked as a spy for Richard III.
The hero, Henry Morane, a fictional character, is chief clerk to John Kendall, a real historical figure who was Secretary to King Edward IV, and held the same position under Richard Duke of Gloucester when he was first Lord Protector and then King Richard III. Morane becomes involved in spying for the King on the intrigues and plots of treacherous barons such as Sir William Stanley and of the King's rival, Henry Tudor (later Henry VII).
Effectively Morane is a sort of 15th century Yorkist James Bond.
This is the first in a trilogy of books about his adventures, which consists of:
The book contains a large amount of historical detail, some true, some speculation, usually described in an entertaining and accessible way.
Richard III has been presented by Tudor propaganda as a monster and tyrant, and the murderer of his nephews, the Princes in the Tower. Henry Morane is clearly devoted to him and does not share that view, part of the story being around his attempts to discover and bring to justice the real murderers.
Most novels dealing with this period tend either to portray Richard III either as a near saint (An example being the brilliant "The Daughter Of Time" by Josephine Tey) in which case they usually depict Henry VII as a monster, or else to portray Richard as something close to the ruthless murderer presented by Shakespeare. This book and the subsequent Henry Morane novels are unsual in that they are sympathetic, without being sycophantic, to both Richard III and Henry VII.
All in all this is an entertaining book, but perhaps not one to be taken too seriously.