As the Great War engulfs Europe, sixteen-year old Ruby Archer decides to 'do her bit' at a local munitions factory, quickly making new friends on the deafening factory floor. But wartime is hard for everyone, and she cannot ignore the sick and injured animals scavenging in the East End streets. Ruby soon takes in injured terrier Mac, and rescues a stray kitten, Tess, but when all the cats mysteriously disappear from the factory, she knows she needs to do more, and with the help of her friends plans a small-scale monthly clinic. Soon opposition comes from all sides, can Ruby and her friends pull together to make her sanctuary dream come true?