Three generations of musical-theater royalty come together in this, one of the last of the big 60s musicals. In the lead, you've got Julie Andrews; and in supporting roles are Carol Channing and Beatrice Lillie.
The setting is 1922 Manhattan, and Millie Dilmount (Andrews) has just arrived in search of a husband. Her plan is to find a job as secretary to an eligible bachelor and marry him. Among her housemates at the Priscilla Hotel ("for single young women") is Miss Dorothy Brown (Mary Tyler Moore), who insists on being addressed as "Miss Dorothy" and dreams of a career on the stage.
James Fox and John Gavin are on hand as the romantic interests, and are ideal as broad caricatures of (respectively) boyish enthusiasm and manly pulchritude. Channing brings her unique persona to the role of weathy socialite Muzzy, and Lillie, while clearly past her prime, shows flashes of greatness as Mrs. Meers, the villainous hotel manager. (And Lillie didn't make many movies, so this is one of the few chances we have to see her work at all.)
A movie like this depends on its star; Andrews is in almost every scene, and she's delightful. It's always a joy to hear that impeccable, crystalline voice of hers, and she's ideal for this part, in which she's torn between the man she loves and the man she thinks she should love.
There are flaws, to be sure. The portrayal of the Chinese bad guys is offensive even by 1967 standards. Mary Tyler Moore is badly miscast; she's far too intelligent and sexy a presence to be believable as the naive Miss Dorothy. And the last 45 minutes or so drag a bit, as the story moves away from the romantic plots to the white-slavery story.
Those problems keep Thoroughly Modern Millie from joining the ranks of the great movie musicals, but it's still a pleasant piece of fluff, and I enjoyed it more than I'd expected to.