Ô mon bel inconnu [1] is a comédie musicale in three acts (four tableaux) composed by Reynaldo Hahn with a libretto by Sacha Guitry.
[2] The plot concerns the wife, daughter and maid of a Parisian hatter, who all reply to his 'lonely heart' advert, and takes place in Paris and Biarritz.
Henry Malherbe, in a review in Le Temps highlighted the overture (which quotes the second finale), two airs for the men in the first act - recalling Manon and the Wedding March, the (title) waltz song for the women, the 'Téléphonage' in strict counterpoint, concluding that Hahn fulfils all the listener's expectations.
[4] Prosper Aubertin, the owner of a hat shop in Paris, bored with his business and the quarrels and frustrations of home life, places a personal ad in a paper stating « Monsieur, célibataire, désire trouver âme sœur.
The Aubertins get back together, Prosper persuades Marie-Anne that the man with whom she was exchanging letters was Claude (who has arrived to ask for her hand), and Victor pairs off with Félicie.