In a quiet countryside, inside an old farmhouse, lives a mother mouse named Mrs. Brisby. She is determined to protect her family at all costs, especially her sick son, Timmy. However, her home is in danger due to the imminent plowing of the farm, which means they will have to move. Desperate to find a solution, Mrs. Brisby embarks on a dangerous adventure to seek help.
In her search, she encounters a mysterious community of rats that have been subjected to scientific experiments in a government laboratory. These rats, endowed with intelligence and unusual abilities, have created their own underground home, but not everything is as it seems. Through her meeting with Nicodemus, the wise leader of the rats, Mrs. Brisby uncovers deep secrets about science and the dangers of power.
As the threats to her home intensify, Mrs. Brisby must decide whether to trust the rats and their knowledge or to face the challenges ahead on her own. Her bravery and determination will lead her to discover the true value of friendship, loyalty, and the sacrifices a mother is willing to make for her children. With captivating animation and a profound emotional backdrop, this story goes beyond being a simple animal tale, becoming a reflection on the struggle between nature and science, and the true meaning of home.