On Halloween night, a teenage chimney sweep named Lubicchi encounters a guy who has been miraculously produced out of rubbish. Lubicchi, by giving him the name Poupelle, is able to rebuild a link he lost when his father succumbed to the tyranny of the Inquisitors—an oppressive group that seeks to repress outside information and the town's actual past. But their newfound connection quickly attracts a lot of attention, and the danger of the Inquisitors, as well as the condemnation of a few locals, will put the duo's friendship to the test. Despite this, Poupelle has struck a particular chord with Lubicchi, and the two collaborate to bring the truth to light and remove the chimney smoke that covers the town's skies.