Some secrets lie just beneath the surface in Florence, Italy. The city that was
once a Roman military settlement flourished, to become the birthplace of the
Italian Renaissance. However, the transformation came with a price, paid by
artists and patrons alike. Enlightened individuals were imprisoned for their
innovation. Master architects concealed plans to protect them from theft. Royal
patrons used hidden stairways and secret passages to protect privacy and to spy
on government and family. Now, as modern innovators employ new science to unlock
centuries-old mysteries, National Geographic reveals the clandestine side of
Renaissance Florence.