"I Am the Walrus" is a song by the Beatles released in November 1967. It was featured in the Beatles' television film Magical Mystery Tour (MMT) in December of that year, as a track on the associated British double EP of the same name and its American counterpart LP, and was the B-side to the number 1 hit single "Hello, Goodbye". Since the single and the double EP held at one time in December 1967 the top two slots on the British singles chart, the song had the distinction of being at number 1 and number 2 simultaneously.

John Lennon received a letter from a pupil at Quarry Bank High School, which he had attended. The writer mentioned that the English master was making his class analyse Beatles' lyrics. (Lennon wrote an answer, dated 1 September 1967, which was auctioned by Christie's of London in 1992.) Lennon, amused that a teacher was putting so much effort into understanding the Beatles' lyrics, decided to write in his next song the most confusing lyrics that he could.

The lyrics came from three song ideas that Lennon had been working on, the first of which was inspired by hearing a police siren at his home in Weybridge; Lennon wrote the lines "Mis-ter cit-y police-man" to the rhythm and melody of the siren. The second idea was a short rhyme about Lennon sitting amidst his garden, while the third was a nonsense lyric about sitting on a corn flake. Unable to finish the three different songs, he combined them into one. The lyrics also included the phrase "Lucy in the sky," a reference to the Beatles' earlier song "Lucy in the Sky with Diamonds."

The walrus refers to Lewis Carroll's poem "The Walrus and the Carpenter" (from the book Through the Looking-Glass). Lennon expressed dismay upon belatedly realising that the walrus was a villain in the poem.

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