from the credits:
This scenario was written by Dean Engelhardt and published in the Chaosium Digest, Volume 29, Number 12 (January 2000).
from the introduction:
This scenario pits the Investigators against a terrible and sinister plot instigated by a mysterious and possibly inhuman power. Investigators with some prior experience of the Cthulhu Mythos will find their knowledge gives them a slight advantage. Little, however, will prepare them for the terrible awakenings that soon take place both within themselves and in a dark and hidden site unknown to man.
The hideous events detailed herein are nominally set in Arkham and Boston during the Spring of 1928. However, the Keeper needs to change little to relocate the scenario elsewhere or to a different year.