A highly intelligent chimpanzee named Caesar has been living a peaceful suburban life ever since he was born. But when he gets taken to a cruel primate facility, Caesar decides to revolt against those who have harmed him.

After their parents are killed in a terrible accident, the four McMurrin children live with their loving Aunt Martha. Martha wants to adopt the children but the town's bitter old banker stands in their way. However, the children's courage and ingenuity triumph and they become a family just before the holidays.