A remake of the French comedy Monsieur Sans-Gene, One Rainy Afternoon gets under way when film-actor Phillippe Martin (Francis Lederer) heads to a darkened Parisian movie theater for a romantic rendezvous with his married sweetheart Yvonne (Countess Live de Margaret). But our hero sits in the wrong seat and kisses the wrong young lady: Monique Pelerin (Ida Lupino), the daughter of a powerful publisher Joseph Cawthorn. This innocent mistake snowballs into a national scandal, fomented by the hatchet-faced president (Eily Malyon) of the Purity League, with Phillippe earning the onus of "The Kissing Monster." It all culminates in one of those zany courtroom trails which proliferated in screwball comedies of the 1930s, wherein Phillippe defends himself by insisting that it is in a Frenchman's nature to be romantic, even with perfect strangers -- and as a result he becomes an international hero! One Rainy Afternoon was the first of a handful of United Artists talkies personally produced by studio vice-president Mary Pickford.
by Hal Erickson synopsis