If you have read Confrontation with Evil about the case which inspired The Exorcist you will know what this is a picture of. Give you a hint it is a hallway described at the end of the book. What resided behind those double doors at the end of the hall has been one of the most kept secrets in paranormal history.
Read the book which was featured in The New York Post and The Sun. It has been called the definitive book on the 1949 possession case which inspired The Exorcist.