St. Thomas's College Cambridge, has a ghost - or so some people believe. How to deal with the sightings on F staircase is an issue that bitterly divides the fellows. And when the Psychic Investigation Unit is called in and a professor collapses with a heart attack during the proceedings, the college really is in a fix. So Nathaniel Gye is called in to make discreet investigations. As he tries to tease out the twisted strands of this strange affair anonymous letters arrive claiming that this unquiet spirit did not commit suicide 10 years previously, but was murdered...