My first critique has to be about the music. Andre Previn's instrumental score is gorgeous. But as far as Lerner and Loewe music goes, it falls short. The singing is mostly rhythmic talking. While the underlying instrumentals have a melody, most of the lyrics are not melodic. The title song "Gigi" is probably the best one but the opening number "Thank Heaven for Little Girls" is underwhelming and the lyrics are a little creepy sung by the aging Maurice Chevalier. The framing is a little awkward too, with Chevalier smack in the center of the shot sitting still just staring into the camera. His is the only character that breaks the fourth wall at the beginning and end of the film to introduce the scene and to close the story.
The actors all put on French-ish accents, but to me they all sound quite different. Chevalier's accent sounds the most traditionally French. Leslie Caron and Louis Jourdan both sound kind of stuffy and maybe a little more British than French. And they all live a stereotypical French lifestyle. Caron plays a quirky, awkward, and naive girl that sort of flails around. The premise is that her grandmother and great aunt have the immense task of taming her and transforming the clumsy Gigi into a lady. It happens in the end rather suddenly, seemingly missing something in the middle. The movie is also pretty blatantly sexist to a modern viewer, reinforcing gender roles and subverting Gigi's sense of freedom. There's not too much depth to the story; it's rather light and predictable.
Lastly, what the film does best is in the art. The movie makes great use of the French scenery. And the lavish sets and costumes are beautifully extravagant, notably Gigi's red themed apartment.
