A group of professional detectives challenge Nancy to tackle a mystery that they have failed to solve: find an invaluable message hidden by a missionary centuries ago in a hollow oak tree in Illinois. While searching the woods for the ancient tree, Nancy and her friends live with a group of young archaeologists who are excavating prehistoric Indian burial mounds on a nearby farm. A shadowy enemy stalks Nancy and harasses everyone at the dig. The young investigator pursues her dangerous adversary to an outlaws’ cave, and is threatened when she discovers an unusual treasure. How Nancy, with few clues to go on, solves this complex mystery will thrill all readers.
- ISBN10 0448095122
- ISBN13 9780448095127
- Publish Date 1 October 1935
- Publish Status Active
- Publish Country US
- Publisher Penguin Putnam Inc
- Imprint Grosset & Dunlap Inc.,U.S.
- Format Hardcover
- Pages 192
- Language English
- URL https://penguinrandomhouse.com/books/isbn/9780448095127