March, 1919. The commissioner of police at New Scotland Yard has a task for Divisional Detective Inspector Hardcastle of A Division: find Lily Musgrave, the missing daughter of Ausen Musgrave MP. Hardcastle, aided by Detective Sergeant Charles Marriott, discovers that the headstrong Lily provides risque entertainment for a number of ex-officers. When she return home of her own accord, however, Hardcastle assumes the case is closed and turns his attention to arranging the finer details of his daughter Maud's wedding. But no sooner is the wedding over than Lily Musgrave goes missing again. And this time, finding her might not be so easy.