The Mystery of Edwin Drood by Charles Dickens was the last work of the author and has been widely discussed and written about not only for that reason but also because it was unfinished and thus poses something of a problem for critics and readers. The book is thus a mystery in a double sense, leaving the reader uncertain whether Dickens intended that John Jasper was the murderer of his nephew Edwin Drood.

… how Dickens started the novel in the usual way by writing the first two installments. The ideas that were behind this story had been written in Dickens’s notebook some time before. The idea of two young people who had been separated for many years after having been pledged to be married was written down as early as 1861 or even 1857, and by the middle of 1869 he was hard at work developing his…