Of Tangible Ghosts

In the first book of L. E. Modesitt, Jr.'s Ghost Books series, "Of Tangible Ghosts," the story is set in an alternate reality where ghosts are real and tangible. When two ghosts and the records of a murdered researcher come into his life, former spy and current professor Johan Eschbach becomes entangled in a web of secrets involving advanced de-ghosting technology. As he navigates this strange world, Johan must confront powerful forces determined to control or eliminate the mysteries he uncovers.