Paranormal investigators Nick Groff and Katrina Weidman spent their lives pushing past the boundaries of fear to find answers about the paranormal. Now, they're going one step further and will confine themselves in some of the most haunted locations for 72 straight hours. They're looking for groundbreaking evidence about the supernatural, and what better way to find it than living with the dead for three days. Although the locations of these lock-ins are famous for being haunted, many have never been filmed, and some will be investigated for the first time ever.