Leonardo’s Secret Notebook | McDonald’s

Leonardo’s Secret Notebook, our new book in the McDonald’s and Hachette Super Club of Adventurers series.

During the 2026 summer vacation, with every Happy Meal, kids will join Chloé, Mila, Ethan, and their dog Oslo—four intrepid little heroes united in a mysterious adventurers’ club—on missions that will have them having fun while traveling through time and to the four corners of the world.

In “Leonardo’s Secret Notebook”, you must find Leonardo da Vinci’s invention notebook, manage to escape from his house, and help him finish his new flying machine!