Sgt. Pepper opens with the title track, starting with 10 seconds of the combined sounds of a pit orchestra warming up and an audience waiting for a concert, introducing the illusion of the album as a live performance. The musicologist Kenneth Womack describes the lyric as "a revolutionary moment in the creative life of the Beatles" that bridges the gap – sometimes referred to as the Fourth wall – between the audience and the artist. He argues that, paradoxically, the lyrics "exemplify the mindless rhetoric of rock concert banter" while "mock[ing] the very notion of a pop album's capacity for engendering authentic interconnection between artist and audience". In his view, the mixed message ironically serves to distance the group from their fans while simultaneously "gesturing toward" them as alter egos, an authorial quality that he considers to be "the song's most salient feature." He credits the recording's use of a brass ensemble with distorted electric guitars as an early example of rock fusion. MacDonald agrees, describing the track as an overture rather than a song, and a "shrewd fusion of Edwardian variety orchestra" and contemporary hard rock. The musicologist Michael Hannan describes the track's unorthodox stereo mix as "typical of the album", with the lead vocal in the right speaker during the verses, but in the left during the chorus and middle eight. "Sgt. Pepper" was the first Beatles track that benefitted from the production technique known as direct injection, which according to Womack "afforded McCartney's bass with richer textures and tonal clarity". The song's arrangement utilises a rock and roll orientated Lydian mode chord progression during the introduction and verses that is built on parallel sevenths, which Everett describes as "the song's strength". The five-bar bridge is filled by an Edwardian horn quartet that Martin arranged from a McCartney vocal melody. The track turns to thepentatonic scale for the chorus, where its blues rock progression is augmented by the use of electric guitar power chords played in consecutive fifths.
McCartney acts as the master of ceremonies near the end of the "Sgt. Pepper's Lonely Hearts Club Band" track, introducing Starr as an alter ego named Billy Shears. The song then segues into "With a Little Help from My Friends" amidst a moment of crowd cheer that Martin had recorded during a Beatles concert at the Hollywood Bowl. Womack describes Starr's baritone lead vocals as "charmingly sincere" and he credits them with imparting an element of "earnestness in sharp contrast with the ironic distance of the title track." Lennon and McCartney's call and response backing vocals ask Starr questions about the meaning of friendship and true love. In MacDonald's opinion, the lyric is "at once communal and personal ... touchingly rendered by Starr [and] meant as a gesture of inclusivity; everyone could join in." Womack agrees, identifying "necessity of community" as the song's "central ethical tenet", a theme that he ascribes to the album as a whole. Everett notes the track's use of a major key double-plagal cadence that would become commonplace in pop music following the release of Sgt. Pepper. He characterises the arrangement as clever, particularly its reversal of the question and answer relationship in the final verse, in which the backing singers ask leading questions and Starr provides unequivocal answers. The song ends on a vocal high note that McCartney, Harrison and Lennon encouraged Starr to achieve despite his lack of confidence as a singer.
Despite widespread suspicion that the title of "Lucy in the Sky with Diamonds" contained a hidden reference to LSD, Lennon insisted that it was derived from a pastel drawing by his four-year-old son Julian. A hallucinatory chapter from Lewis Carroll 's 1871 novel, Through the Looking-Glass, inspired the song's atmosphere. McCartney confirms the existence of the drawing and Carroll's influence on the track, noting that although the title's apparent drug reference was unintentional, the lyrics were purposefully written for a psychedelic song. The first verse begins with what Womack characterises as "an invitation in the form of an imperative" through the line: "Picture yourself in a boat on a river", and continues with imaginative imagery, including "tangerine trees", "rocking horse people" and "newspaper taxis". Martin describes the introduction's melody, which he regards as "crucial to the staying power of the song", as "a falling scale in the left hand, a rocking scale in the right." In his opinion, the verse might have sounded monotonous if not for the juxtaposition "of that almost-single-note vocal against the inspired introductory notes", which he describes as "mesmeric, compelling". In Womack's view, with the merging of Lennon's lyrics and McCartney'sLowrey organ introduction "the Beatles achieve their most vivid instance of musical timbre". The musicologist Tim Riley identifies the track as a moment "in the album, [where] the material world is completely clouded in the mythical by both text and musical atmosphere." According to MacDonald, "the lyric explicitly recreates the psychedelic experience". Lennon explained: "It was Alice in the boat. She is buying an egg and it turns into Humpty Dumpty. The woman serving in the shop turns into a sheep and the next minute they are ... in a rowing boat and I was visualizing that. There was also the image of the female who would someday come to save me – a 'girl with kaleidoscope eyes' who would come out of the sky. It turned out to be Yoko ... so maybe it should be 'Yoko in the Sky with Diamonds'."
MacDonald considers "Getting Better" to contain "the most ebullient performance" on Sgt. Pepper. Womack credits the track's "driving rock sound" with distinguishing it from the album's overtly psychedelic material; its lyrics inspire the listener "to usurp the past by living well and flourishing in the present." He cites it as a strong example of Lennon and McCartney's collaborative songwriting, particularly Lennon's addition of the line: "couldn't get much worse", which serves as a "sarcastic rejoinder" to McCartney's chorus: "It's getting better all the time". McCartney describes Lennon's lyric as "sardonic" and "against the spirit of the song", which he characterises as "typical John". MacDonald characterises the beginning of the track as "blithely unorthodox", with two staccato guitars – one panned left and one right – playing the dominant against the subdominant of an F major ninth chord, with the tonic C resolving as the verse begins. The dominant, which acts as a drone, is reinforced through the use of octaves played on a bass guitar and plucked on piano strings. McCartney's bass line accents non-roots on the recording's downbeat.
Womack interprets the lyric to "Fixing a Hole" as "the speaker's search for identity among the crowd", in particular the "quests for consciousness and connection" that differentiate individuals from society as a whole. MacDonald characterises it as a "distracted and introverted track", during which McCartney forgoes his "usual smooth design" in favour of "something more preoccupied". He cites Harrison's electric guitar solo as serving the track well, capturing its mood by conveying detachment. McCartney drew inspiration for the song in part from his work restoring a Scottish farmhouse. Womack notes his adaptation of the lyric: "a hole in the roof where the rain leaks in" from Elvis Presley's "We're Gonna Move". The song deals with McCartney's desire to let his mind wander freely and to express his creativity without the burden of self-conscious insecurities.
In Everett's view, the lyrics to "She's Leaving Home" address the problem of alienation "between disagreeing peoples", particularly those distanced from each other by the generation gap. McCartney's "descriptive narration", which details the plight of a "lonely girl" who escapes the control of her "selfish yet well-meaning parents", was inspired by a piece about teenage runaways published by the Daily Mail. It is the first track on Sgt. Pepper that eschews the use of guitars and drums, featuring a string nonet with a harp and drawing comparison with "Yesterday" and "Eleanor Rigby", which utilise a string quartet and octet respectively. While Richard Goldstein's 1967 review in The New York Times characterises the song as uninspiring, MacDonald identifies the track as one of the two best on the album. Moore notes that the writers judge the work from "opposing criteria", with Goldstein opining during the dawn of thecounterculture of the 1960s whereas MacDonald – writing in 1995 – is "intensely aware of [the movement's] failings".
Lennon adapted the lyric for "Being for the Benefit of Mr. Kite!" from an 1843 poster for Pablo Fanque's circus that he purchased at an antique shop in Kent on the day of filming the promotional film for "Strawberry Fields Forever". Womack praises the track's successful blending of a print source and music: "The interpretive power of the mixed-media application accrues its meaning through the musical production with which the group imbues the Ur-text of the poster." MacDonald notes Lennon's request for a "fairground production wherein one could smell the sawdust", an atmosphere that Martin and Emerick attempted to create with a sound collage that comprised randomly assembled recordings of harmoniums, harmonicas and calliopes. MacDonald describes the song as "a spontaneous expression of its author's playful hedonism". Everett thinks that the track's use of Edwardian imagery thematically links it with the album's opening number.