Watch the Nicholas Brothers dance the "Jumpin' Jive" in the 1943 musical, Stormy Weather. Fred Astaire said it was "the greatest dancing he had ever seen on film."
From The New York Times:
For it wasn't the acrobatics, in themselves, that made the Nicholas brothers the Nicholas Brothers. It was the overall beauty and musicality of the entire dance. Their achievement was in the how — the way Fayard would deploy his hands, as graceful as Fred Astaire's; the way Harold would make every silhouette superclear; the genial, noncompetitive way each brother would cede the floor to the other for a solo, passing the dance like a baton, in musical time. When Astaire pronounced their "Jumpin' Jive" number in the movie Stormy Weather (1943) — unrehearsed and achieved on the first take — to be the greatest dancing he had ever seen on film, he was not commending the acrobatics alone but rather the way the brothers erupted organically out of their tap steps, like a series of overlapping geysers that, simply to look at, project an observer into a stratosphere of elation.