The line comes from I Am the Walrus, a 1967 Beatles song written primarily by John Lennon and released on the Magical Mystery Tour EP and album. Lennon borrowed its dreamlike imagery from Lewis Carroll and built the track around wordplay and surreal nonsense, ending with the repeated goo goo g'joob chant. Over decades the phrase became a shorthand for Beatles psychedelia, quoted in films, sampled in music, and reused online as a knowing nod to the band's strangest era, still instantly recognisable even to listeners who do not know the full song.