Hitchcock wants a party in a haunted house. At the last minute the ad agency finds one. But when they expect ambience (with their special sound effects) they get real ghosts. A good character study. Real people are portrayed very closely to their reported personalities ( from bios or news reports ) with realistic interactions with each other, the fictional characters and the ghosts. The haunts are based on real people and their interactions set this novel at a high level of readability and enjoyment.
ignore the audio listing --- I read the hardback version once