While Brooklyn temporarily stays with her parents in Northern California, she visits the caves hidden deep under their commune. A room is unearthed, revealing a treasure trove of artwork, rare books and cases of wine, a chest of jewellery. and a perfectly mummified body. They also find a secret map leading to even more valuables. Word of the explosive find draws in reporters, art appraisers, questions and complications. Soon Brooklyn decides to do a little excavating of her own and solve the mystery of the treasure before anyone else is written off.