Celebrate the fun that grandparents and grandkids can get up to in this action-packed undersea adventure, a companion picture book to Paul McCartney's #1 New York Times bestseller Hey Grandude. Grandude's inventions are the stuff of legend, and his new green submarine doesn't disappoint. In fact, it flies as well as submerges! Grandude whisks the grandkids off on another adventure, but he and the Chillers soon find themselves in a pickle. Suddenly, it's Nandude to the rescue! Nandude is an explorer as courageous as Grandude, with an amazing accordion-ship to boot! Between Grandude's magic compass and Nandude's magical music, everyone arrives home safely. But not before enjoying a parade, dancing rainforest animals, and a narrow escape from a grabby octopus. This tale is perfect for little explorers and Paul McCartney fans alike! Artist Kathryn Durst returns with glorious, humor-filled illustrations that are as beautiful as ever.