Peter McKay

After a chance meeting and an indiscreet conversation, childhood friends Tommy Beresford and Tuppence Cowley become involved in a convoluted intrigue led by a mysterious man known simply as Mr. Brown.

After finding her boss, a private detective, has committed suicide and has left her his agency, Cordelia Gray is asked to investigate the suicide of the man's son. During the course of her investigation, Cordelia becomes obsessed with the young man's memory and his increasingly suspicious death.