A self-effacing prizefighter assumes a very different attitude once he hits the big time.

Peggy and Bill are high society lovebirds, but their marriage plans are put on hold while Peggy spends most of her summer straightening out her wayward parents and her unlucky-in-love sister Janet. Mama and Papa are set to rights fairly quickly, but Janet's the one with real problems. It seems she sent some compromising love letters to a worthless cad, and now the bounder wants to use the letters for blackmail. Peggy's friend Roger and his flapper sweetheart Tootie hatch an elaborate plan to retrieve the incriminating letters and salvage Janet's reputation.

A man who believes that love is more animal and chemical than spiritual, bets that by controlling the circumstances, he can get any man and woman to fall for with each other and get engaged within a month.

The author of a book on eugenics attempts to prove his theories by having his childless sister and her husband adopt the child of a “physically superior” chauffeur and housemaid, leading to comedic complications when the parents refuse to give up their child.