The renowned creators of One World: 24 Hours on Planet Earth follow up with a lyrical book exploring the wild wonders of the sea—and how the oceans of our big blue planet converge as one, teeming with life.Two children and their grandmother discover a “sea heart” on the beach: a smooth, round bean the size of one child’s palm, which has traveled the world on the Gulf Stream’s current. The trio traces the bean’s wondrous journey on a map—through seagrass meadows brimming with turtles and tiger sharks, coral reefs, underwater mountains traversed by whales, and kelp forests bobbing with seals—until it washes up, a full year later, on their rainy beach in Scotland. Narrative nonfiction at its best and most beautiful, this companion to One World from zoologist Nicola Davies and award-winning artist Jenni Desmond is a fluid, well-researched story about the way currents connect us all to the vast ocean that colors our planet blue. Tackling, too, the global impact of humans on the ocean—especially the perils of plastic—the book employs fascinating facts, gentle urgency, and specific conservation success stories to point a wise and hopeful path forward.