First off, its two stars. Fred Astaire and Audrey Hepburn. What more needs to be said? Astaire was well in to his second stardom as a leading dancer/actor or film musicals, not to mention being an icon of American ease and style that very few men have exemplified since. And Hepburn was very much aglow as the elfin yet elegant star of light comedies at Paramount. Each of them would gain significantly from their on-screen teaming. Astaire would actually get a character to play other than an entertainer; Hepburn would finally get to show off her dance skills in an American-made film.
Then there is great support from Kay Thompson as an acerbic fashion magazine editor and the incredible fashion statements of Hubert de Givenchy. Thompson is a husky-voiced, horsey delight as she stomps and strides through this role. She and Hepburn get a duet, which some may consider a primer on how to set back the feminist movement. So what? It's witty and it's cute and it's got great steps that the two sparkle as they execute.
Then de Givenchy's gowns and day ensembles. They are exemplary of 1950s fashion and each is more gorgeous than the next! They are photographed with the utmost care and taste by Ray June. And it didn't hurt that Donen had fashion photography maven Richard Avedon as visual consultant on the film. Just as Blow-Up and Darling would symbolize the 1960s from a fashion standpoint, de Givenchy's designs say a lot about the 1950s. I am almost sure that de Givenchy was rewarded with a nomination from the AMPAS for his designs. If he wasn't he deserved it.
The dances are choreographed by quite a few sources. Astaire, obviously, did his own thing. Many of the other numbers were staged by estimable choreographer Eugene Loring. The number in the Paris jazz club has been quoted in commercials and even Whitney Houston was given a go-around in slinky balck turtleneck and jeans for her 1991 video "I'm Your Baby Tonight".
Though Donen's Paris doesn't scream color like Kelly's did in 1951, he still brings romance, Gershwin and great talent together in to a romantic and lush whole.