It's 1220 and the City of London is a dirty and dangerous place, very different to the peaceful monastery of Saint Wilfred's in Saint Agnes Next-the-Sea. But when the new abbot returns from Westminster Abbey, it seems that he brings back something wicked, plunging Saint Wilfred's into deceit and violence. Once again, it falls to trainee monk Tom Fletcher to find the true culprit in a matter of life and death.