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