Castle Conundrum Author:Franklin W. Dixon AN ANCIENT HIDDEN TREASURE STIRS UP A CUNNING PLOT! Teen Village International brings Frank and Joe to the south of France to rebuild a deserted town. The finished project will be a center for refugee children. But word is that the local castle is haunted -- by the centuries-old ghost of its lord, who hid a fortune in diamonds from bandi... more »ts within its thick stone walls. Spooky lights, strange noises, and several close shaves convince the Hardys that someone is trying to sabotage the project. A pair of French twins, descendants of the owner, want to save the castle from developers. Every facet of the case leads to a dead end -- and the Hardys are hunting a desperate enemy!« less