When Bella is anonymously sent the photograph of a cafe with the words, 'This is the key, ' penned on the back, she travels to Italy to discover why. A key to what? Why is she being shadowed? And, what does it have to do with a dangerous riddle set out during WWII? Follow Bella and her friends on their farcical scramble across Italy to uncover a thrilling secret that had been hidden for centuries."