Finally: The long-awaited revelation! What happened to Flavia's mother? It is a spring morning in 1951. Flavia de Luce has gathered with her family at the Bishop's Lacey train station to await the return of her mother Harriet, who went missing while climbing in Tibet. As the train arrives, a tall stranger approaches the eleven-year-old amateur detective and whispers a cryptic message to her. Moments later, the man is dead - someone from the crowd has apparently pushed him in front of the train. A new case for Flavia de Luce, who this time even takes to the skies to catch a killer, and finally learns the truth about her mother's past...