Robert and Nina Tracey resolve to live separate lives when their eight-year marriage dissolves into disagreements and divorce. But their separate attempts to get back out on the dating scene have a funny way of bringing them together.

Lorelei Lee is a beautiful showgirl engaged to be married to the wealthy Gus Esmond, much to the disapproval of Gus' rich father, Esmond Sr., who thinks that Lorelei is just after his money. When Lorelei goes on a cruise accompanied only by her best friend, Dorothy Shaw, Esmond Sr. hires Ernie Malone, a private detective, to follow her and report any questionable behavior that would disqualify her from the marriage.

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.

A former OSS agent is assigned to rescue two atomic scientists from the dastardly Russians and spirit them away from behind the Iron Curtain.