Deep, deep down, at the very bottom of the ocean, lies a secret world. Through lyrical narration, this spare-text STEM picture book takes readers on a journey to a place very few humans have ever been—the Mariana Trench. The imagined voyage debunks scary myths about this mysterious place with surprising and beautiful truths about life at Earth's deepest point. Deep, Deep Down shows a vibrant world far below, and teaches readers how interconnected our lives are to every place on the planet.