Man in the Brown Suit

Anne came to London looking for adventure. In fact, adventure finds her at Hyde Park Corner tube station. Anne is present on the platform when a man loses his balance and is electocuted on the rails. The Scotland Yard verdict is accidental death. But Anne is not satisfied. After all, who was the man in the brown suit who examined the body? And why did he race off, leaving a cryptic message behind: ‘17-122 Kilmorden Castle’?