Design for Living (1933)

This movie, which is much less well known than Lubitsch's 'Ninotchka', is in my opinion a far funner movie to watch.  And in the romantic comedy genre, enjoyment is the name of the game.  The movie script is a very loose adaptation of Noel Coward's popular stage play, but Lubitsch and his writer, Ben Hecht used only one line from the original play. Really, they kept the idea intact, which is a long term menage a tois between two men who are very good friends and a woman who loves them both and cannot choose between them.

Gina (Miriam Hopkins) meets George (Gary Cooper) and Tom (Frederic March) on a train.  She is working as an illustrator for advertising and they are a struggling painter and play write, respectively.  Max, Gina's boss, is clearly over the moon about her, but she is much more attracted to the two handsome strangers she has met.  She has a go with each of them, and even after that, she still cannot decide, so they decide to swear off sex and work on their careers.  Which is wildly successful in terms of fame and fortune, but they are still stuck, with Gina unable to choose between the two friends. 

The movie is witty and fun, and risque for the time, I would think.  They talk about sex and sleep in big beds, so there is no hiding what is going on--it predates the Production Code by a couple of years, which made prudishness the law, which may explain how it manages to look much more modern than other older movies, and just shows that sex has always sold well.