THOROUGHLY MODERN MILLIE: roadsters, Gatsby-style parties, daredevil stunts, candy-striped biplanes, flapper fashions, and a subplot involving white slavery that could have come from any old Saturday serial.
Eager young Millie Dillmount (Julie Andrews) is determined to keep up with the trendsetters in the Roaring 20s. "I don't want to be your equal any more – I want to be a woman". She arrives in New York City to a women's hotel run by Mrs. Meers (Beatrice Lillie), who also runs a white slavery ring. Millie is intent on finding a job as a secretary with a rich, handsome, eligible boss. Deciding to adopt the appearance of a flapper, she has her hair bobbed.
Millie does get a job with a handsome boss, Trevor Graydon (John Gavin), but he has eyes only for Miss Dorothy (Mary Tyler Moore), and Millie is forced to make do with Jimmy Smith (James Fox), a paper-clip salesman.
After they've returned to the hotel from attending a party at the Long Island estate of wealthy Muzzy van Hossmere (Carol Channing), Millie finds that Miss Dorothy has disappeared. When she and Jimmy detect the scent of opium in Mrs. Meers's room, they realize she has a sideline. The valiant Jimmy must go in drag to uncover the whereabouts of the white slavers' hideout.
The film’s funniest moment is when Andrews vamps it up in her boss's office.