Changsheng's father brings home a homeless tabby kitten. However, as the kitten grows older, they realize that it's actually a little tiger. Soon Changsheng and the little tiger become so attached to each other. Wearing a tiger-head hat made by his mother, Changsheng and the little tiger become best brothers. However, the villagers are scared of the tiger. Changsheng has no choice but to send the little tiger back to the mountains. The little tiger promises that it will return in times of need. All Changsheng has to do is to put on his tiger-head hat and yell "Tiger Brother" from the top of the mountain. One day a gang of robbers appear in the village. Since the villagers are unable to resist the robbers, Changsheng runs up to the top of the mountain, yelling for his tiger brother. The tiger brother and his brave tiger friends arrive to their rescue, driving away all the robbers out of the village. The tiger brother returns to the mountains, but it keeps its promise to Changsheng forever. A story about bravery, love, and promise, it also introduces the characteristics of people born in the Year of the Tiger, the origin of the Siberian tiger, and the history of the tiger-head hat.