Hope Cahill, Amy and Dan's mother.
(SPOILER ALERT) On the 39 clues, after you collect the clue copper, you learn that Hope Cahill hid this clue in a microchip and hid that on the right side of her left wrist, concealing the clue in her left arm.
Amy Cahill hid a clue in her arm in "The 39 Clues" series. She had a small microchip implanted under her skin which contained a vital clue to the location of the 39 Clues treasure.
Tomas.
On the 39 clues, in the My Cards section and the My Clues section, you learn that the Tomas branch of the Cahill family hid the clue cocoa in the mountains of Machu Picchu, Peru.
morroco
the Tomas
David Livingstone
Tomas
Tomas
Tomas de Torquemada hid a clue in Victor Falls for the 39 Clues series. He was a powerful Grand Inquisitor during the Spanish Inquisition and was known for his ruthless tactics in dealing with heretics.
In his secret labratory, hidden behind a bookshelf is his Smiljan, Croatia home.
In the book series "39 Clues," Nikola Tesla hid his clue in Krakatau, an island in Indonesia that was known for its volcanic eruption.