"Glass Onion" is a song by the Beatles from their 1968 double-album The Beatles primarily written by John Lennon and credited to Lennon–McCartney.

The song's "the Walrus was Paul" lyric is both a reference to "I Am the Walrus" and Lennon saying "something nice to Paul" in response to changes in their relationship at that time. Later, the line was interpreted as a "clue" in the "Paul is dead" urban legend that alleged McCartney died in 1966 during the recording of Sgt. Pepper's Lonely Hearts Club Band and was replaced by a look-alike and sound-alike. The line is preceded with "Well, here's another clue for you all".

Lennon himself dismissed any deep meaning to the mysterious lyrics:

I threw the line in—"the Walrus was Paul"—just to confuse everybody a bit more. It could have been "The fox terrier is Paul." I mean, it's just a bit of poetry. I was having a laugh because there'd been so much gobbledygook about Pepper—play it backwards and you stand on your head and all that.

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