Madeline Lane, co-owner of Boston's Coda Gems, had never been interested in the 1946 theft of the Duchess of Windsor's jewelry in the UK, an odd but famously unsolved burglary, one that years later still had few clues and zero suspects.

But Madeline's sister, Shay, a dewy-eyed romantic, is fascinated by the crime, especially when a photography gig she'd just lined up in the UK is next to the scene of the theft in Sunningdale. Once Shay arrives in Sunningdale, she begins asking questions and is immediately injured in a 'car accident' that was no accident, and the deaths begin. Madeline flies to the UK to be with her sister in the hospital and becomes intrigued by the unlikely old theft.

What the sisters don't realize is that a treacherous secret was behind the burglary from the Duchess years before, with powerful UK institutions still ready to kill to hide the truth, and then a reporter from the Times of London working on an article about the long-ago burglary dies in a fall from a train.

Madeline connects slim leads from an old police report with new information she uncovered, and she digs in a moldering Sunningdale grave. There is a confrontation and a tragedy.