On a horse ride into town a young girl Isa Cofield gets her aging grandfather, J.D. Cofield, to tell her of his adventures in the old west. Along with an old Indian friend of J.D.'s, they embark into their own adventure to not only solve the mystery of a hidden ghost town called Pueblo del Diablo, (Town of the Devil.) but to solve a murder mystery and a thirty-year-old train robbery.