Cyd Charisse

Who can forget the impact of Cyd Charisse's appearance in the Broadway Sequence in the film "Singing in the Rain"? It was simply sensational. Pauline Kael talked about her "unleashing her legs". Then, the success of this dance performance deep in people's minds, the film industry came up with a similar sequence in "The Band Wagon" when again she unleashed her famous 10 million dollar (insured) legs. As Fred Astaire said in the words of the Mickey Spillane detective he was playing as he met her in the down-and-out bar: "she came at me in sections; she had more curves than a scenic railway."
The dance sequence I recall that was more sensational than either of those, though not quite so sexy, was the boxing training session in "It's Always Fair Weather". It is a work of art. It has humour, excitement, classical ballet sections together with broad Hollywood musicals work; it has dance effects that are simply beyond belief. I don't think there is anything to compare with it for sheer entertainment, skill and unforced athelticism in the form of easy-going dance.
They say she wasn't much of an actress. So? So what? She didn't need to act, just to dance.
As Fred Astaire said: "When you danced with Cyd, you stayed danced with."
I think she helped change the style of classical ballet and made it sexy, and at the same time transformed Hollywood films dance routines to make them more balletic.