There is a species of Victorian mystery story that is as pure an expression of nineteenth-century rationalism as you are likely to find. A strange event occurs which, at first glance, appears to admit no rational explanation; by the end of the story, it is revealed to have a logical explanation after all. Thus foolish superstition is banished by the pure light of reason. But there is another side to late-Victorian fiction of the unexpected, represented by Henry James’s ghost tale The Turn of the Screw (1898): a darker, slipperier, and far more unsettling narrative in which the supernatural elements are never satisfactorily explained and are charged with menacing psychological overtones.