The Leper of Saint Giles is a medieval mystery novel by Ellis Peters, set in October 1139. It is the fifth novel in The Cadfael Chronicles and was first published in 1981. The book includes a map of the Abbey, the town of Shrewsbury, St. Giles, the winding River Severn and its small local brooks, and places in the environs mentioned in this story and others in the series. It was adapted for television in 1994 by Central for ITV.