According to the American College Dictionary, terror "implies an intense fear which is somewhat prolonged and may refer to imagined or future dangers." When Alfred Hitchcock chooses stories to arouse terror, he is meticulously faithful to this definition.

Does a haunted house frighten you? A contest between a man and a rat? Possession? Witchcraft? Does your blood chill when you think of someone being deliberately driven mad? How about a man who becomes half man, half fly? How about a tree that screams when you cut it down? Or a room that shrieks when no one is in it?

Alfred Hitchcock has chosen twenty-one stories, two novelettes, and a complete novel guaranteed to terrify most normal people and even some abnormal ones. As everyone knows, he is a specialist in the macabre and bizarre. Askes to explain his approach to fictional crime, he wrote:

"The blunt instrument, the gang murder, the paid assassin have always seemed to me positively indelicate. Murder is a fine art and needs the embellishment of a sophisticated imagination. The true aficionado prefers to have his nerves ruffled by the implied thread--the Borgias rather than the Syndicate. What is more delightful than a domestic crime, when it is executed with subtlety and imagination? I leave to other more pedestrian talents materials based on newspaper accounts. True crimes, ugh! Alas, most of them are dull and give no evidence of the careful planning and loving thought that should go into any human activity as rewarding as murder."