MANSFIELD — Daylight was expiring outside as I stood alone in a Mansfield Reformatory hallway connected to a maze of rooms in what used to be administrative offices. A film crew and paranormal investigator had departed the third floor, heading up a stairwell to the chapel. Positioning a cellphone between my fingers, I stayed behind and captured a photo of a bedroom that had been featured in the movie "The Shawshank Redemption," when from a darkened corridor emerged a faint, whispery voice: "What are you doing?" A chill passed through my body, goosebumps prickling my skin. Questions filled my head: Did the sound materialize from a dimension or realm beyond this world? Was it spoken by the spirit of a former inmate? Did the voice belong to another member of the group? Or was it a trick of the imagination?