Act 1 of the Ghoul Island Saga begins with a storm at sea. After making it to shore the characters are plagued by nightmare visions of the End of All Things.
Rescuing their crewmates, recovering the cargo, and investigating the source of the visions brings them face to face with all manner of undead horrors.
Certain spells and monsters in this adventure come from Sandy Petersen's Cthulhu Mythos. While it is possible to play the adventure without that material, some adjustment will be required. SPCM also contains the core mechanics of a Cthulhu Mythos game, including special skills, languages, races, and classes, rules for Dread and Insanity, and a full bestiary. It's very much recommended, to get full enjoyment out of any Cthulhu Mythos adventure.