Gambler Nathan Detroit has few options for the location of his big craps game. Needing $1,000 to pay a garage owner to host the game, Nathan bets Sky Masterson that Sky cannot get virtuous Sarah Brown out on a date. Despite some resistance, Sky negotiates a date with her in exchange for bringing people into her mission. Meanwhile, Nathan's longtime fiancée, Adelaide, wants him to go legit and marry her.

Jerry Mulligan is an exuberant American expatriate in Paris trying to make a reputation as a painter. His friend Adam is a struggling concert pianist who's a long time associate of a famous French singer, Henri Baurel. A lonely society woman, Milo Roberts, takes Jerry under her wing and supports him, but is interested in more than his art.