Perhaps no sonic flourish epitomizes the spirit of the Beatles -- and indeed the entire British Invasion -- more than the jubilant 12-string guitar chord that opens "A Hard Day's Night." (That George Harrison chord, incidentally, is Gm7 add 11.) It was that chord, and song, which introduced the movie of the same name, a film that in turn embodied Beatlemania at its apogee. "A Hard Day's Night" had a depth and shimmer to the production greater than any previous Beatles track, due in large part to that 12-string guitar. The song itself mirrored the Beatles' boundless enthusiasm more than almost anything else Lennon-McCartney wrote, particularly when McCartney joined Lennon in the closing lines of the verse, singing of getting home to their loves and feeling alright with a joy and anticipation that is downright fierce. Effective juxtaposition of bridge and verse is a Beatles specialty, but on "A Hard Day's Night" they outdid even themselves, as the Lennon-sung verse yields to a more wistful, haunting bridge sung by McCartney. McCartney is one of the greatest upper-register singers in rock & roll, and he was rarely better or more effervescent than he was when he reached the bridge's climax in "A Hard Day's Night." The instrumental break was garnished by an imaginative keyboards by producer George Martin, and the fade closed on a series of an eerie unaccompanied circular 12-string guitar notes by Harrison. Lyrically the title of "A Hard Day's Night," allegedly taken from a comment by Ringo Starr, was the first instance of a Beatles lyric to reflect Lennon's love of puns (which was reflected much more strongly in his 1964 book In His Own Write). The body of the actual lyric, sung by a guy who doesn't mind slaving away at work to buy his lover goodies since she makes him feel so good when he comes home, might not be so apropos today, when women have much more presence and equality (in the workplace and at home) than they did in the mid-'60s. It might be getting a little too hung up on PC mores to dwell on that; certainly the main point of the song was to express an overall joie de vivre, and it excelled at doing so. It was also a big smash, reaching number one in both the U.S. and U.K. The most noteworthy cover version was a live one by Otis Redding, who (as he did with songs by both the Beatles and the Rolling Stones) accentuated its funkiest and most soulful properties, managing to make it over into a soul tune without embarrassing either himself or the composers.