Penguin Books. Having seen a depressed polar bear in the zoo, Grandfather and his dog, Roo, set off on an expedition to find the last polar bears. After a treacherous journey on HMS Unsinkable, they reach Walrus Bay and the fun really starts. Howling wolves and terrible snowstorms delay the start of their trek and when they're on the way their tent is blown away by the fierce winds. They struggle on, hungry and cold to the top of Great Bear Ridge where they see the polar bears at last.