Terry Scott, a young archaeology professor, seeks Nancy\'s help in unearthing a secret of antiquity which can only be unlocked by three Black keys.
Nancy and her friends follow a tangled trail of clues that lead to the Florida Keys and finally to Mexico in this suspense-filled story that will thrill readers..
Pitt.
Pitt Terry tells Nancy of his suspicions of the Tinos, a Mexican couple posing as scientists who vanished the same night as Dr.
Before the professor had time to translate the cipher, the tablet disappeared - along with Dr.
The Clue was a cipher carved on a stone tablet.
Joshua Pitt came across a Clue to buried treasure.
While on an archaeological expedition in Mexico, Terry and Dr.
Terry Scott, a young archaeology professor, seeks Nancy\'s help in unearthing a secret of antiquity which can only be unlocked by three Black keys
