One of the Beatles’ more whimsical/lightweight songs was “When I’m 64,” but that tune was probably more noteworthy because it was on the band’s iconic Sgt. Pepper’s Lonely Hearts Club Band album.

That 1967 masterwork had song styles that were all over the map, and while the Beatles had alluded to going beyond cutesy pop tunes on albums like Rubber Soul and Revolver, no one was prepared for the milestone that Sgt. Pepper’s was (and still is).