The story concerns a famous flea circus. At the center of the story are a clown flea named Francois and a glamorous flea named Fifi. Francois asks Fifi to marry him, but she refuses. One day, the performance of the circus's show-stopping dance number is interrupted by a dog, who the entire entourage takes to, leaving the owner now bankrupt and with no actors. Francois assures the owner of the circus that he will help. Trailing the dog, he finds it in a nearby fountain, the fleas on his back sinking into the watery depths like people on a sinking ship. Among the fleas calling for help is Fifi. Francois saves her, to which she asks him to marry her for his bravery. Soon afterward, the two marry and have a rather large number of baby fleas. Returning to the flea circus owner, he is more than happy to display Fifi, Francois, and their offspring, and the circus is back in business. Everything looks to be back to normal, when Francois walk into Fifi's room and see her working away at a pair of knitting needles. Apparently, the circus is about to get a whole lot more crowded.