Riko Rinda (Haruka Ayase) is an appraiser with her own store "All-Around Appraiser Q". She is hired as a temporary employee by The Louvre for a Mona Lisa exhibition to be held in Japan. Yuto Ogasawara (Tori Matsuzaka) is a magazine editor and follows Riko Rinda for a story. The two soon discover a hidden puzzle of the Mona Lisa.