Theo's Tricks: and other Greek Yarns

Cora is kidnapped, and her mother, Demi, accompanied by another daughter, Sophia, starts out to find Cora. The two think they know who has kidnapped Cora. They know they must find Uncle Theo, who will help them. Early in the search they find a golden ball which Uncle Theo has left for them. They become assured that Uncle Theo will leave clues along the way for them to follow. The clues are tricky and unexpected, but they lead Demi and Sophia on a series of adventures and at last they find Cora, but Cora is not the same person she was when she was kidnapped.