It was 1964, and the Beatles were huge. Someone had the foresight to capture it on film, and boy did they do it brilliantly! There was no ridiculous love story or anything of the sort to try to make the music and the musicians interresting. Richard Lester realized that the exciting thing about The Beatles was that they were The Beatles. And he just took it from there. And yes, Ebert called it a Great Movie.
And the opening shot gets us right into it. It's exciting and iconic, even moreso when you hear rousing title song with the images. Here they are: The Beatles, the greatest group of all time, running from a mob of screaming fans. Excitement shows on every face.