A Quote from Portal 2
Ooh. It's dark down here, isn't it? They say that the old caretaker of this place went absolutely crazy. Chopped up his entire staff - of robots - all of them robots! They say at night you can still hear the screams - of their replicas. All of them functionally indistinguishable from the originals... No memory of the incident... Nobody knows what they're screaming about. Ab-solutely terrifying. Though obviously not paranormal in any meaningful way.