In an old church on a cold autumn afternoon, a young woman is making a brass rubbing. Suddenly, she senses a presence by the altar. A vague, diaphanous object brushes past her. She bends down over her brass rubbing and sees that it is speckled with blood. She faints. What do you do when your girlfriend says she's seen a ghost? Brian Kenning is a physicist, so he decides to perform an experiment in the church to find out what she actually saw. He becomes the first person to truly uncover the mystery of ghosts and how their appearance is linked to historical events. His explanation involves a new theory about the quantized nature of time itself. But Brian and his colleagues pursue the truth too far, until the safety of all is threatened. The consequences of their later experiments are most mysterious, and it is left to Brian's brother, John, to uncover the truth and rue the day they ever discovered the time quantum.