A jewelled Anglo-Saxon reliquary has mysteriously appeared on a website, apparently containing a relic of St Eldreda herself. The nuns at St Eldreda's Abbey are understandably curious, and invite Libby Sarjeant to look into the matter in more depth. Fascinated by the story, Libby's friend Peter obtains permission to mount 'Murder In The Monastery', a play based on St Eldreda's story, excitingly set in the ruins of the original monastery. Unfortunately for Peter's plans, a real body is discovered, and Libby and her friend Fran find out that this is sadly not the first. Together, Libby and Fran dive into their investigations, to hopefully find the link between the relic, St Eldreda, and the pile of bodies.