Standing outside a bakery shop in Rio, Ginger Rogers asks, "Oh, Freddie, how do you ask for little tarts in Portuguese?" Fred Astaire replies, "Don't heckle me, try the Culbertson System." This pre-Code, double entendre joke would have been funny to Depression-era audiences, for whom bridge was a common pastime. Ely Culbertson was a champion bridge player and worldwide celebrity, who had won several international tournaments by developing a rather aggressive bidding system. He was also notorious for his sexual exploits. His 1940 autobiography was banned in many countries. In the 1930s, the word "tart" was equivalent to "slut" or "whore". Also, in the opening inspection of hotel staff, the boss sees a maid whose shoe heels are oddly beveled and says he will not tolerate that sort of thing. A "round-heeled woman" was 1930s slang for a prostitute, a woman who could tilt easily from standing to being on her back.
Despite his obvious on-screen chemistry in dancing with Ginger Rogers, Fred Astaire was reluctant to make a second movie with her. He had previously been part of a dance duo with his sister, Adele Astaire, but wanted to establish himself as a solo dancer. After this film, Astaire sent a note to his agent about Rogers. "I don't mind making another picture with her, but as for this team idea, it's out! I've just managed to live down one partnership and I don't want to be bothered with any more." But when the critics praised the Astaire-Rogers pairing in "Rio", Astaire was persuaded, and he and Rogers soon made the second film in their partnership, La Joyeuse Divorcée (1934).
Originally conceived by RKO as a vehicle for Dolores Del Río, this film is most notable for its star-making pairing of Fred Astaire and Ginger Rogers. In supporting roles, the two relative unknowns smoked up the screen in a dance number called "The Carioca". It generated such a positive response from critics and fans that they were eventually reunited in nine subsequent films.
In the "Flying Down to Rio" musical number, many of the girls on the airplane wings are wearing see-through tops. The Hays code, introduced in 1930, was not enforced until 1934.