Auction House manager Sophie receives an oil painting and delves into its history. She enlists the help of Sam and Martijn and learn about three monks and their secretive journey over four-hundred years ago. Planned by a priest in the past, in the present world, clues come to light about a treasure and about others who will stop at nothing to possess it. Terri, a young Museum Curator, and Tammy from New York, join Sophie in a search that spreads from the Bosporus in the east to the Bay of San Francisco in the west. Their quest takes them to Florence, Italy, where they must use their combined knowledge that they have gathered to solve the ancient mystery surrounding a princess. Three keys, three clues, three locks to choose, will the riddle be solved? Will the treasure be found?