The film opens in 1986 on Nippon Farm with a cat named Moth Ari who has given birth to kittens. One of the kittens is named Milo (lit. Brown tiger (チャトラン, Chatoran) in the Japanese version), and has a habit of being too curious and getting himself into trouble. He finds a pug puppy named Otis (プー助 (Pūsuke) in the Japanese version), and they soon become friends. When Milo is playing inside a box floating in the river, he accidentally drifts downstream. Otis runs after Milo. Milo goes on many adventures, escaping one incident after another.
He encounters Bear, escapes from Raven that infested Deadwood Swamp, steals a dead muskrat from Fox, follows a train-track of a train named Nippon Bearway to the home of Deer, who shelters him, sleeps in the nest with Owl, stays for a while with Pig and her piglets, catches a fish, only to have it stolen by Raccoon, is mobbed by the Seagulls, and evades Bear, then Snake, then falls into an old pit.
Otis, for his part, follows Milo throughout, usually only an hour behind and less than a mile out of range. Finally, the two catch up with one another. While Milo is in the hole, Otis pulls him out by means of a rope. Milo and Otis are reunited, and soon find mates of their own: Joyce, a white cat, for Milo, and Sondra, a French pug, for Otis. After this, they part ways and raise puppies and kittens of their own. Milo, Otis, Joyce, and Sondra find their way back together through the forest to their barn and the credits roll.
Sound Effects Used
- Hollywoodedge, Sheep Baa Medium Pers PE027001
- Hollywoodedge, Single Cow Moo CRT011601
- Sound Ideas, BIRD, ROOSTER - ROOSTER: TWO CALLS, ANIMAL
- Sound Ideas, HORSE - INTERIOR: WHINNY, ANIMAL 01