Belles de la Nuit is one of René Clair's dream-reality mixtures in which a young music teacher … struggles to become a successful composer, find true love, fend off the machine age, retain his sanity. All this with one foot in kaleidoscopic dreams and the other on a banana peel.
The belles of the title are four beautiful women [the music teacher] meets in his dreams. They belong to different periods in French history, the salient characteristics of which are broadly satirized. These lovelies, of course, are inspired versions of the women he knows in real life….
Clair keeps his melange from flying apart by interweaving recurring elements. Each shift to an earlier period of French life is prefaced by an old gentleman denouncing the France of his old age and extolling the one of his youth—the French period Clair satirizes next….
The music [the teacher] composes, which accompanies him in his dream voyages, is melodic and nostalgically romantic—the very antithesis of the cacophonies of contemporary life, which Clair satirizes most of all.
Alexander Singer, "Film Reviews: 'Belles de la nuit'," in Films in Review (copyright © 1954 by the National Board of Review of Motion Pictures, Inc.), Vol. V, No. 4, April, 1954, p. 191.