In medieval Cambridge four children are murdered. The Catholics blame the Jews and they are placed under the protection of the King Henry VIII. The king sends for someone to do a scientific investigation into the deaths. The person sent is an Italian woman doctor, but in medieval Cambridge she must conceal her true identity to keep herself safe.

"England. 1191. After the death of her friend and patron, King Henry II, Adelia Aguilar is living comfortably in retirement and training her daughter, Allie. Learning the practical knowledge of anatomy, forensics, and sleuthing that catches murderers, Allie is already a skilled healer, with a particular gift for treating animals. Her father, Rowley, Bishop of Saint Albans, and his patron, the formidable Queen Eleanor of Aquitaine, have plans to marry Allie to an influential husband. When a friend in Cambridgeshire falls ill, Allie's path crosses with Lord Peverill, a young aristocrat who would be a most suitable match for the young healer. Allie learns a village girl has disappeared-- and over the past few months, several girls from the villages surrounding Ely have vanished. A monstrous predator is on the loose-- will Allie's stubborn pursuit of the truth help her find the killer... or make her the next victim?"--Provided by publisher.