It's 1940 and Nazi bombs are raining down on London, but 13-year-old bike messenger Jack has just discovered something unbelievable: a stray dog with a surprising talent. Jack navigates the smoky, ash-covered streets of London amid air raid sirens and falling bombs, dodging shrapnel and listening for cries for help, as a bike messenger for fire crews. When Jack finds a dog, miraculously still alive after the latest Nazi bombing...