Templar Bascot de Marins in preparing to rejoin the Holy Wars when he is called upon to investigate a gruesome murder in the Order's own chapel. The shocking discovery of a strangled prostitute in the Templar chapel throws the Order into disarray. Alongside the corpse is a purse containing 30 pence - the same amount of silver Judas received for betraying Christ. Is the murder revenge for a Templar brother's betrayal? Has one of their own broken his vow of chastity? The Order's preceptor turns to Bascot to determine whether a murderer walks in their midst.
