In a swell of sea-linked essays, Christina Rivera explores the kinship between marine animals, humans, and Earth's blue womb. Rivera's investigative questions begin with the toxic burden of her body and spiral out—to a grieving orca, a hunted manta ray, a pregnant sea turtle, a spawning salmon, an "endling" porpoise, and the "mother culture" of sperm whales—as she redefines what it means to mother and defend a collective future.