Just for the record, yes, that’s the immortal Frank Nelson (uncredited) as the announcer, and Gene Kelly (who codirected with Stanley Donen), Dan Dailey and dancer-choreographer Michael Kidd in a rare acting gig near the beginning. The music is by Andre Previn, best known these days as a conductor and arranger, with lyrics by Betty Comden and Adolph Green, who wrote every single golden word in this movie and, as far as I’m concerned, deserved the Nobel Prize for World Literature, though that’s probably just me.