Trixie Belden and her best friend Honey are exploring an old gatehouse when they unearth a diamond hiding in the dirt. Has a jewel thief come to Sunnyside? Discover Trixie Belden, the teenage detective who has been charming readers for generations.

Trixie Belden loves to explore, and this time, she and Honey have their sights on a run-down old gatehouse. Far more than cobwebs and dust wait for them inside because buried in the dirt is...a diamond!

How could anyone have forgotten such a precious jewel? Trixie is convinced a thief walks among them. And this treasure hunt leads to two likely suspects: the manor houses' new gardener or chauffer.

Detectives Trixie, Honey, and their best friend Jim reunite for a caper that sparkles with danger.

Peek into the adventurous world of Trixie Belden and unravel book three in the mystery series that has delighted decades of readers.