Sarah Taylor, a police psychologist, meets a mysterious and seductive young man, Tony Ramirez, and falls in love with him. As a cause of this relationship, she changes her personality when she begins to receive anonymous telephone calls.
Hilton Cubitt, from Derbyshire, consults Holmes about a series of dancing men picture-messages his wife is receiving. On their wedding-day, she had made Cubitt promise he would ask her nothing about her past, but she now seems to be terrified. Holmes has to decipher the code of the matchstick men and get to the bottom of a dreadful murder which lies behind it.