From the publisher:
The Sevenfold Path is a sourcebook and campaign for classic-era Call of Cthulhu.
Investigators will travel to 1920s Iceland, be introduced to the legend of Olaf Ulfsson, and investigate the ruins of the abandoned Third Cloister. The encounter rival lodges of the theosophy movemenet in Reykjavik, and get a chance to butt heads with some of the proto-Nazis of the Thule Gesellschaft.
It they are not wise and clever, they will be dead or corrupted.