After six months of research, adventure seekers Bowen McAlister, Cyrus Curran, Duff Gentry, and Lockhart Dawson make their way to Boulder, Colorado, to explore the abandoned gold mine Ruby Lode. But when they arrive, Duff, a born psychic, senses something isn't quite right—and the closer they get, the more his unease grows. Something long buried in the deep shafts and drifts of Ruby Lode makes its presence known by exposing dark, guarded secrets. Preying on the adventurers' weaknesses and insecurities, Ruby Lode's own destructive secret threatens their sanity, friendship, and ultimately their lives. Bo, Cy, Duff, and Lockey must work together to unravel the century-old mystery before they become another footnote in the mine's history.