Spawn of Azathoth: Herald of the End of Time

Astronomers have theorized that our sun is not alone in its journey around the galaxy, but is accompanied by an unknown second star of dim radiance. This second star, while perhaps invisible from Earth even with the finest optics, would periodically pass close enough to our solar system to have far-reaching effects upon the evolution of this planet. This is a campaign-length adventure for 4-6 experienced investigators. The suspicious death of a former teacher draws the investigators into an adventure with cosmic import.