How would you get mail if you lived in the middle of the sea? It's Jo's dad's job to deliver it, taking bottles wherever they need to go. He always comes home with exciting stories to tell―but Jo is far too afraid to go out on the ocean herself. Until Dad gets a bad sea cold, that is. With no one but Jo to deliver the bottles, she must find her courage and set sail alone. As she embarks on her mission, her fears just might be replaced with new friendships . . . and grand stories of her own.