Frost investigates the murder of a 15 year old girl who disappeared while completing her newspaper round. He also has to look into vandalism at a local churchyard as Supt. Mullett fears it might be the work of satanists but it is also where the 15 year old's body is found. He also has to deal with Mrs. Compton who has been receiving threatening phone calls. The Comptons are dealers of rare books and keep a large and valuable inventory in their home. When Mr. Compton is killed in a house fire, Frost quickly has a prime suspect. Finally, Frost receives a visit from his late wife's sister who now lives in America and doesn't seem to be in any hurry to return.