This feature-length animated satire on Disney's Fantasia follows a series of cartoon shorts from Bruno Bozzetto, including Opera and Self-Service. Allegro Non Troppo takes six famous musical pieces and animates them with remarkable comic invention. Debussy's 'Afternoon of a Faun' becomes a tale about an old, lustful faun who can't find any willing nymphs, until the birds and butterflies come to his help. Ravel's 'Bolero' shows the creation of life in a discarded Coke bottle—the evolution of dinosaurs and their eventual demise. A Vivaldi concerto accompanies a bee winging happily among the flowers until he is disturbed by lovers. Bozzetto's images are far more bawdy than their Disney originals; naked nymphs and satyrs cavort on the screen, lovers roll about in the grass, and a grotesque evolutionary sage appears in the 'Bolero' sequence.

Interspersed with the animation, are live action scenes involving a temperamental impresario, a sensitive artist, and a gross conductor of an orchestra of old ladies in ludicrous finery, who are kept in a cage.