Dark Day in the Deep Sea (Magic Tree House, No. 39)
MARY POPE OSBORNE is the author of theNew York Timesnumber one bestselling Magic Tree House series. She and her husband, writer Will Osborne (author ofMagic 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.