The film is centered around a trio of cats who live in the alleyways of New York City. The cats have distinctive personalities and seek to live their lives in the manner of their own choosing. Grumble-paws is a tom cat who loves to sing to the inhabitants of the city's apartment buildings, but he is continuously pelted by thrown shoes and other objects by the residents. Jem is a cat who loves to catch mice, and she engages in elaborate acts in order to secure for herself the most mice. Herman is a loveable oaf, and likes drinking milk.