How does a history become a story? And how does a story become a ghost story? In The Ghost of the Mary Celeste (Doubleday), Valerie Martin discusses her fascination with the history of the ship Mary Celeste, found floating with no crew off the coast of Spain in 1872. Gradually this history is replaced by diaries and ship's logs. Arthur Conan Doyle even writes a fictional version. For Martin, the empty boat floating in the mist is an image of something from the afterlife passing into this life. She says she does not believe in ghosts - but she does believe in telling a truly haunting story.