What are Notre Dame's gargoyles guarding? What do five ordinary flagstones have to do with one of the most notorious killing machines ever created? What is the Phantom of the Opera's connection to a statue on the Seine? Paris has one of the richest and most exciting histories of any city in the world but some of its most fascinating stories have been lost to the ages. Enjoy this one-of-a-kind tour as we reveal its many secrets, hiding in catacombs and cathedrals, sidewalks and cemeteries, and along its famous river.