These movies are based on true stories that Ed and Loraine Warren;
Edward Warren Miney (September 7, 1926 – August 23, 2006) and Lorraine Rita Warren (née Moran; January 31, 1927 – April 19, 2019) were American paranormal investigators and authors associated with prominent cases of alleged hauntings. Edward was a self-taught and self-professed demonologist, author, and lecturer. Lorraine professed to be clairvoyant and a light trance medium who worked closely with her husband.
In 1952, the Warrens founded the New England Society for Psychic Research (NESPR), the oldest ghost hunting group in New England. They authored many books about the paranormal and about their private investigations into various reports of paranormal activity. They claimed to have investigated well over 10,000 cases during their career. The Warrens were among the first investigators in the Amityville haunting. According to the Warrens, the official website of the NESPR, Viviglam Magazine and several other sources, the NESPR uses a variety of individuals, including medical doctors, researchers, police officers, nurses, college students, and members of the clergy in its investigations.