Cleanliness Is Next to Hitchcockiness

I just got home from the library and caught Alfred Hitchcock being interviewed by Dick Cavett (reruns being broadcast on Turner Classic Movies). Hitch, in reply to a question about viewers of Psycho being afraid to take a shower, relates the story of a man who wrote to him, saying that his daughter, after having seen the French horror film Diabolique, could not take a bath. Then, she went to see Psycho, and could not take a shower, either!

Needless to say, she became "unpleasant to be around."

The Hitch wrote this laconic letter of advice to the man: Dear Sir, please take your daughter to a dry cleaner's...