Boston Metaphysical Society Scourge of the Mechanical Men One-Shot

Granville T. Woods and Nikola Tesla are in a race for time to save Boston from a mysterious disease that turns human beings into soulless machines in this steampunk adventure.
This is the first standalone sequel to the Boston Metaphysical Society series about an ex-Pinkerton detective, a spirit photographer, and a genius scientist who battle supernatural forces in late 1800s Boston.