The Adventurers travel back to Florence in the year 1503. Here the Agents are trying to prevent Leonardo from painting his famous "Mona Lisa". Using many of Leonardo's amazing inventions to chase after The Hacker's evil Agents, the kids are able to save Leonardo who has been kidnapped. During the sitting for her portrait, the kids bring some delicious pastries, causing Signora del Giocondo to come up with her famous smile!