Merlin Mission #38: Monday With a Mad Genius

JACK AND ANNIE are on a mission to save Merlin from his sorrows! Charged with finding the second of four secrets of happiness, the brother-and-sister team travel back in the magic tree house to the period known as the Renaissance. This time, Jack and Annie will need more than a research book and a magic wand. They'll need help from one of the greatest minds of all time. What will they learn from Leonardo da Vinci?

MARY POPE OSBORNE is the author of the New York Times number one bestselling Magic Tree House series. She and her husband, writer Will Osborne (author of Magic Tree House: The Musical), live in northwestern Connecticut with their three dogs. Ms. Osborne is also the coauthor of the companion Magic Tree House Fact Trackers series with Will, and with her sister, Natalie Pope Boyce.

SAL MURDOCCA has illustrated more than 200 children's trade and text books. He is also a librettist for children's opera, a video artist, an avid runner, hiker, and bicyclist, and a teacher of children's illustration at the Parsons School of Design. Sal lives and works in New York with his wife, Nancy.