Lord Astley surprises his wife with a trip to America to see her family before they end their honeymoon adventures. But just as they arrive, they find Grace's sister, Lillias, is the prime suspect in her husband's murder. To add to the confusion a solicitor arrives to tell the sister's they are needed in Scotland immediately to claim their mother's inheritance.

The clock is ticking to clear Lillias of suspicion, but someone is determined to keep the sisters from reaching the Scottish Highlands. When Lillias disappears, Freddie and Grace race to Scotland, sure the answers will be found in a long-forgotten castle.

With a ghost from Frederick's past leaving threatening clues along the way, the mysterious Mr. Kane waiting in the wings to grab the inheritance for himself, and an apparition haunting the infamous castle, Lord and Lady Astley must capture the castle, save Lillias, and not die in the process.

The Highland Heist is a Freddie and Grace Mystery, sequel to The Mistletoe Countess, The Cairo Curse, and The Juliet Code.