Appears in: Strange Tales of Dread & Wonder.
Rolthin Abbey is a combination health spa and spiritual retreat which caters exclusively to the rich and powerful (and the occasional "forgotten derelict" taken from the streets as an act of supreme charity). Its unique treatments offer the promise of adding decades to one's life. The Investigators could be drawn to this idyllic place for a number of reasons ... but is it really all that it seems?
Spoilers - Keepers Eyes Only
Players should not read any further.
Rolthin Abbey is actually a fair bit more than it seems. As well as the (very profitable) business it runs as a health spa and spiritual retreat, the Abbey is a cornerstone of a nefarious plot to turn the human race into Serpent Men.
The Serpent Men have never much cared for humanity: some hundreds of thousands of years ago they experimented with human genetics, placing a marker in the genes of a select group of humans. The genetic variation, when triggered by an elixir, would turn the experimental subject into a Serpent Man. While the experiment was successful, it wasn't particularly useful as so few of the (rapidly expanding) human race held the genetic modification. Fast forward a few hundred thousand years to the modern age -- in the intervening time, the process of normal interbreeding has led to the situation where most of humanity now has the Serpent Men's genetic markers.
Sometime in the 1930s, the Serpent Men have re-discovered their ancient plot and are seeking to revive it. Teaming with an American snake-oil salesman called Raynard Japeth (who was drawn to the promise of eternal life), the Rolthin Abbey has been set up as a facility to test the current level of human susceptibility. Unbeknownst to the many pampered guests, all food prepared within the Abbey's walls is imperceptibly laced with the Serpent Men's elixir.
Player Handouts: There are no player handouts.
Locations: Rolthin Abbey is in Vermont.
Creatures: Serpent Men.
Tomes and Artifacts: An underground laboratory has lots of Serpent Man technology.
Campaigns / Scenarios:
Although never written in all-caps, Rolthin is actually an acronym made up of the seven principles which make up the order's (public) manifesto: Righteousness, Order, Love, Temperance, Health, Industry and Naturalness
An appendix to the scenario includes two tables describing the transformation of a human to a Serpent Man.
Unlike most Call of Cthulhu (RPG) scenarios, Rolthin Abbey doesn't have a distinct plot or narrative. Rather it supplies a detailed setting in the form of the Abbey's layout and a variety of key characters. It also supplies some meta-plot seeds that give some ideas as to how the Investigators could be drawn into investigating this unusual place.
This scenario has a very strong 'pulp' feel to it, with the authors likening the desired tone to the pulp fiction of Robert Howard and Edgar Rice Burroughs. There is a very 'black and white' morality to the characters and setting which may not fit into campaigns which emphasize moral shades of grey.
Comments to Keepers about this scenario; Possibly how to run it successfully. Keep general DISCUSSION on the talk page.