It's Queen Georgiana's silver jubilee, and Alice-Miranda and her friends are invited. While Evesbury Palace is every bit as magnificent as they'd imagined, some of the staff are behaving strangely. Edgar and Louis, Aunty Gee's grandsons and the palace's resident mischief-makers, don't exactly give their guests a friendly welcome. When they team up with an unexpected visitor, things soon go from bad to worse.

Behind the scenes it seems something much more sinister is at play. Why is Aunty Gee so determined to keep Alice-Miranda at the palace for the rest of the holidays? And who is her mysterious milliner? With the help of her friends and a trusty butler, can Alice-Miranda uncover what threatens to bring down the royal family?