Which American dancer, singer, actor, choreographer and television presenter supported Jack Buchanan when he performed That's Entertainment! in the musical film The Band Wagon?
That's Entertainment! (song):  The song is performed in the film by Jack Buchanan supported by Fred Astaire, Nanette Fabray, and Oscar Levant. Fred Astaire: Fred Astaire (born Frederick Austerlitz; May 10, 1899 – June 22, 1987) was an American dancer, singer, actor, choreographer and television presenter.
Fred Astaire