This is one of the most sophisticated and funny comedies I've seen in my whole life, thanks to one of the wittiest screenplays ever (by Charles Brackett, Billy Wilder, et al), deft direction by Mitchell Leisen, expertly paced, with a top cast, the best costumes, very elegant sets, etc.
Claudette Colbert is wisecracking chorus girl Eve Peabody (later Baroness Czerny), stranded in Paris, who is befriended by taxi driver Tibor Czerny (played by Don Ameche, in one of his best roles) and ends rubbing elbows with the "smart-set", with unexpected results. For those who have watched Anatole Litvak's "Tovarich" (1937) on TCM, starring Colbert and Charles Boyer, it has a similar premise, but the other way round, because in the latter Colbert, a Russian Grand Duchess who belongs to that country's Royal Family, pretends to be a maid.
The cast is full of excellent players: John Barrymore who impersonates with great skill, Monsieur Flammarion, a role somehow reminiscent of the one he played in "Twentieth Century" opposite Carole Lombard, but in a much "understated" manner. Mary Astor, as his unfaithful wife is rightly "stiff-upper-lip", high class and disdainful. Francis Lederer is very good as her lover, Jacques Picot, who falls under the spell of Colbert's charms. Rex O'Malley is Astor's wisecracking friend, Marcel Renard.
This movie has definitely the trademark "Paramount Look" and the great settings recreate Paris very well. There are many very funny scenes, especially those at the soirée offered by pretentious socialité Hedda Hopper and the party that takes place at the Flammarion Residence in Versailles, where all the guests dance "La Conga". Unforgettable.