The Warrens were not merely curious about the occult. They were devout investigators, deeply convinced that evil exists, and that it manifests itself with an intelligence, cruelty and persistence that many prefer to ignore. Ed Warren was one of the few lay demonologists recognised by the Catholic Church. Lorraine, for her part, possessed gifts she described as clairvoyance and spiritual sensitivity. Together, they plunged into a universe of shadows where others refused to look. This book is not a work of fiction. Nor is it an attempt to convince the sceptic. It is a faithful compilation, based on the original Warren files, interviews, field notes, recordings, books, and eyewitness accounts of the unexplained horror. There are 27 documented cases, selected from thousands for their impact, complexity and resonance.