Madeline is the smallest of twelve girls in a boarding school, in an old house in Paris. When long lost Uncle Horst pays a surprise visit to Madeline, promising to move her to a new home in Vienna, her longing for a family seems to be fulfilled. Madeline becomes suspicious when her new Uncle loses his refined accent and takes an unexplained detour. Knowing she's in trouble, Madeline leaves a trail. It then turns out that Uncle Horst is actually Henri, a miserable lackey who works for an even more miserable woman, Madame LaCroque, who runs a dingy factory. Ultimately, Madeline helps the orphans who work there by notifying the outside world of their plight.