Chinon-chateau of legend, steeped in the history of France and England. It is to Chinon that Emily goes on a long-awaited holiday, to meet her charming but unreliable cousin, Harry. Harry wanted to explore the old town and the castle, where Queen Isabelle, child bride of King John, had withstood the siege of Chinon many centuries ago, and where, according to legend, she hid her casket of jewels. But when Emily arrives at her hotel she finds that Harry has disappeared, and as she tries to find him she becomes involved with some of the other guests and learns of a mystery dating from the German occupation during the Second World War. Another Isabelle, a chambermaid at the hotel, fell in love with a German soldier, with tragic results.

Emily becomes increasingly aware of strange tensions, old enmities and new loves; as she explores the city, with its labyrinthine dungeons and tunnels and its ancient secrets, she comes ever closer to the mystery of what happened to both the Isabelles of Chinon's history.