From puppyhood, Ellie has been trained as a search-and-rescue dog. She can track down a lost child in a forest or an injured victim under a fallen building. She finds people. She saves them. It's what she was meant to do. But Ellie must do more. Her handlers — widowed Jakob, lonely Maya — need her too. People can be lost in many ways, and to do the job she was born to do, Ellie needs to find a way to save the people she loves best.