Percy Byshe Shelley was a haunted man. He saw a man who looked just like him walking on the terrace and the man asked how much longer Shelley meant to be content. Days later, he stood screaming over Mary in the middle of the night about a vision of the sea rising into the house. He saw his doppelganger again standing beside Mary and strangling her. Interestingly, Jane Williams—who was staying with the Shelleys along with her husband, Edward—also reported seeing Shelley's double walking past her window and disappearing around a dead end. Edgar Allan Poe, E. T. A. Hoffman, and the psychologist Otto Rank all shared Shelley’s curiosity with the doppelganger. Do we all have doubles, and, if so, what does it mean for us to come across them?