From the introduction:
This adventure is set near Worbarrow Bay in England and was inspired by M.R. James's story "Wailing Well." The original story says nothing about the origin or nature of the well or its denizens, but the Keeper will find reading it worthwhile.
In this adventure, the investigators will journey to England to aid an old friend who has discovered that his inheritance includes a plot of land stained with a terrible evil. This adventure is challenging, but requires more planning and intelligent action than firepower. The adventure is set in the 1990s, but can be placed in another time period. Keepers running a 1920s campaign might wish to acquire a copy of the story and involve the investigators in the original action.