after this point, the ancestry of shakespeare's version of "hamlet" becomes more difficult to trace. many literary scholars believe that shakespeare's main source was an earlier play—now lost—known today as the "ur-hamlet". possibly written by thomas kyd, the "ur-hamlet" would have been in performance by 1589 and was seemingly the first to include a ghost in the story. using the few comments available from theatre-enthusiasts at the time, scholars have attempted to trace exactly where the "ur-hamlet" might have ended and the play popular today begins. a few scholars have suggested that the "ur-hamlet" is an early draft of shakespeare's, rather than the work of kyd. regardless of the mysteries surrounding the "ur-hamlet", though, several elements of the story changed. unlike earlier versions, shakespeare's "hamlet" does not feature an omniscient narrator of events and prince hamlet does not appear to have a complete plan of action. the play's setting in elsinore also differs from legendary versions.