Paul Doherty's fourteenth novel in the brilliant Hugh Corbett series. Friar Roger's Bacon's book of secrets is coveted in both France and England, but the brilliant, controversial scholar has concealed his discoveries behind a mystifying code. When Sir Hugh Corbett, spy master to King Edward I, instructs his agents to prise the book from its hiding-place in Paris, they succeed only at a violent and bloody cost. A meeting between the scholars of both countries is demanded by Philip IV of France to discuss whether the code can ever be broken, and Edward, bound by his recent peace treaty with Philip, is forced to agree. The meeting takes place at Corfe Castle, which soon becomes a place of murder, mystery and mayhem. Young women from the castle are being slain and then two of the French scholars die in sinister circumstances. Corbett has to thread this murderous maze, whilst at the same time, trying to decipher the secrets of one of England's greatest scholars.