In 1394 Crispin Guest, Tracker of London, is minding his own business at a local tavern when a strange man hands him a wrapped package and then disappears. The man tells Crispin not to open the package in public and that he will know what to do with it. Crispin hurries home, opens the package and finds a very old book. The cover appears newer, but the pages seem to be extremely old. Stranger still, the text is written in a language Crispin does not recognize. Crispin does have a love for books, so he makes his way to a bookseller for help. The bookseller confirms what Crispin already believes ... newer cover, very old pages made of papyrus. The bookseller thinks the text is written in Coptic and sends Crispin to another man for help. The second man sends Crispin to a barber who is able to translate the book. And what Crispin learns is terribly unsettling, both to him and could also be to the doctrine of the Christian church if this book falls into the wrong hands. It appears this is a copy of the Gospel of Judas. Crispin soon finds himself in the middle of three murders ... the three men he visited with this disturbing book. Being a Tracker, he sets out to find the murderer. But others are interested in this book as well, and Crispin finds himself in peril more than once. Can he track down the killers, and what is he to do with this blasphemous book?

TRAITOR'S CODEX in the eleventh book in Jeri Westerson's A Crispin Guest Mystery series. Though I have not had the pleasure of reading any of the other books in this series, Ms. Westerson does an excellent job of relating the backstory about Crispin and some of his adventures as a Tracker (like a private investigator). There is non-stop action and adventure in this thrilling mystery. Events move in a rapid-fire manner for such a historical timeframe. Crispin is a strong main character with a cadre of equally strong and diverse supporting characters. Ms. Westerson ties in just enough actual historical and Biblical reality with this exciting story to keep you turning pages for more.