The Fungi From Yuggoth, softback campaign for Call of Cthulhu, by Keith Herber
“Internationally-famous psychic, Paul LeMond, has disappeared. From the moment your investigators find him, they will be plunged into the black secrets of the sinister Brotherhood of the Beast and its inhuman masters. The investigators must traverse the globe in an effort to track down the manifestations of the Brotherhood and to find when the Day of the Beast is planned. The investigators will visit four continents and possibly an alien planet in search of occult mysteries, madness, and grisly death.
This book contains a complete campaign in eight chapters for Call of Cthulhu.”