While exploring an ancient storage room of the Great Gummies, Tummi discovers a mechanical decoy used to make dragon footprints, but accidentally starts the ignition on the machine and begins bouncing all across the land.
The footprints attract a real dragon, who proves to be different from the stereotype of the large monsters.
The Knights of Dunwyn also see the machine and believe it to be a real dragon that needs to be killed in order for the kingdom to be safe.
- The title is a reference to the song "Someday My Prince Will Come" from Snow White and the Seven Dwarfs.
- The illustrated storybook Tummi and the Dragon (and audio tape/record) from the Disney Read-Along series, is based on this episode.