Fromage wishes to continue the family tradition of being a rat chaser on a ship but Mama Cat feels that rat catching is not a ladylike profession. When Fromage sneaks off to begin her adventures, she makes friends with an orphaned Scottish rat named Aloysius much to the dismay of her conventional Mama. Papa cat, however prepares his daughter and her new friend for a life of excitement by having a young lad named D'Artagnan teach them both how to swordfight. When they travel to meet the Queen of France, they meet up with a very lovely but naughty mermaid and a band of robbers. All of their quick thinking and sword fighting skills are needed to insure their survival.