Think of a number by John Verdon

[Jacqui]

A retired police detective is contacted by an old college friend who has received some threatening letters from an anonymous source who seems to be able to read his mind. The detective is intrigued by the puzzle of the case can't resist involving himself in the investigation. The story read like an overheard conversation which made it easy to follow and I couldn't pick the murderer till the end! A very enjoyable read indeed.