Bart receives an anonymous letter warning him that his life is in danger. This episode was the beginning of what was to become a continuous stalking storyline between Sideshow Bob and Bart Simpson.

References:
The entire theme, including the music and title, is an obvious reference to the movie Cape Fear.
Ned Flanders is seen cutting his hedge in a parody of A Nightmare On Elm Street.
There is also a re-enactment of the torture scene from James Bond's Goldfinger.
Robin Williams is seen watching this episode in the 2002 movie One Hour Photo.

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