1192. Returning from the Holy Land at the end of the Third Crusade with Richard the Lionheart, King of England, Sir John de Wolfe, a Devon knight, finds England simmering with rebellion. Discovering a body washed up on the shores of the River Exe, its throat cut, Sir John deduces that he was a king's courier. Tasked by Hubert Walter, the Chief Justiciar, to find out why the man died and who killed him, Sir John de Wolfe finds himself drawn unwillingly...