The game uses many elements from Lovecraft's The Dunwich Horror and The Shadow over Innsmouth. The Necronomicon, as well as Lovecraft himself (under a different name), make cameo appearances in the game, along with well-known actors such as Jack Nicholson and Vincent Price.
The game takes place in 1910, and concerns the visit of a young British photographer, John Parker, to the isolated New England town of Illsmouth (an alteration on Lovecraft's Innsmouth) to witness and photograph the passage of Halley's Comet.
In 1834, on the last passing, Lord Boleskine visited the town after learning that certain conditions near the town would allow astronomical objects to be seen clearer and closer than on any other spot on earth. He decides to test this theory by observing the comet from Illsmouth, but something unexpected happens and he goes insane, spending the rest of his life in a London lunatic asylum. John Parker, learning of the 1834 incident and reading over Boleskine's papers, wishes to succeed where his predecessor failed.
When he arrives, Parker stumbles upon a sinister conspiracy and must survive the three days between his arrival and the comet's passage while finding out what happened in 1834." (Wikipedia)
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