A widowed mouse, Mrs. Frisby, attempts to save her family by acquiring some help from the well-taught rats of NIMH. Having no one to help her with her problems, a widowed mouse visits the rats whose former imprisonment in a laboratory made them wise and long lived.

Tien Pao is all alone in enemy territoy. Only a few days before, his family had escaped from the Japanese army, fleeing downriver by boat. Then came the terrible rainstorm. Tien Pao was fast asleep in the little sampan when the boat broke loose from its moorings and drifted right back to the Japanese soldiers. With only his lucky pig for company, Tien Pao must begin a long and dangerous journey in search of his home and family.