The Secret Hangman by Peter Lovesey
Peter Diamond, the Bath detective, is having woman trouble. His boss wants him to find a missing person, the daughter of one of her friends in the choir. He is not enthusiastic. Another woman, who calls herself his Secret Admirer, wants to set up a meeting in a local pub. He tries ignoring her. Then there is sexy Ingeborg Smith, the ex-journo detective constable, distracting the murder squad from their duties. No one ignores Ingeborg. Murder becomes a possibility when a woman's body is found hanging from a playground swing in Sydney Gardens and a suspicious second ligature mark is found around her neck. Diamond investigates the victim's colourful past. More hangings are discovered and soon he is certain that a secret hangman is at work in the city ...