When Max drops by the local museum to visit his dinosaur friends, they're all gone! It seems that T. Rex, his dinosaur pals, and Dinosaur Dora have gone on tour to museums around the world. Max is disappointed that he missed them, but his mom says, "Why don't you write a note to T. Rex? I'm sure he'd love to know you were here." So begins the latest chapter of this pen pal relationship that spans the ages and includes the adventure of a lifetime. The dinosaurs travel to the jungle, through the desert, and across the frozen tundra, with stops on a sandy beach and in a city with buildings so tall that even T. Rex feels small. It's all very thrilling . . . so why does T. Rex have that funny feeling in his tummy? Why can't he wait to get back to the museum? Can Max help him feel better? Like the best friends that they are, T. Rex and Max share thoughts, dreams, jokes, and dinosaur trivia in this heartwarming book that includes real cards and letters to open.