Caleb Armitage, the 'gentleman Bow Street runner', finds that being knighted is no picnic. The Prince of Wales requires Jane and Caleb to attend the start of the season; and when an old acquaintance turns up, it appears that the prince has an ulterior motive. He hopes that the intrepid pair will be able to elucidate the reasons for a number of supposedly accidental deaths. When Lady Lieven presents tickets to Almack's, it appears that she also has an investigation she wishes Jane in particular to carry out. Add to that a sabotaged Draisine, or hobby horse, and Jane and Caleb find themselves very busy in a world of glittering leisure and pleasure.