A Summer of Discontent (Matthew Bartholomew Chronicles)

In is 1354, and the Bishop of Ely has been accused of a most terrible murder. Glovere was steward to Lady Blanche de Wake, a close relative of the King. A malicious gossip, his body was discovered days after the Bishop had publicly threatened him. Protesting his innocence, the Bishop summons Cambridge proctor Brother Michael to help clear his name. When Michael and his friend, Matthew Bartholomew, inspect the body, they realize someone has stabbed him quite precisely in the back of the neck. When two similar murders are discovered, it is clear that whoever the murderer is, he is getting better and better at his modus operandi.