Mark Keyes is a retired Pennsylvania State Police Criminal Investigator and former volunteer firefighter/EMT who is working currently as a private detective. Mark is the Director of the Pennsylvania Paranormal Association (The PPA) in which Mark has worked with his team on over 200 paranormal resolution cases while taking a look at the psychological aspects of hauntings and helping clients recover from extreme hauntings. Mark has been a contributor for Paranormal 911 and Haunted Hospitals TV series on Travel Channel in the U.S. and Travel & Entertainment Channel in Canada. Mark has also authored two books Chasing Shadows: A Criminal Investigator’s Look into the Paranormal and The Upper Darby Poltergeist, with a third book on the way. For more information visit www.the ppa.net