Paul McCartney has revisited an early, largely forgotten Beatles song, admitting it isn't a great composition but remains one of his personal favourites for sentimental reasons. The track, "One After 909", was one of John Lennon's earliest songwriting attempts, written when he was around 17 or 18, and its resurrection on the band's final recorded album offers a rare glimpse of Lennon and McCartney's raw, pre-fame songwriting partnership rather than their later, more polished work.

The Beatles first tried to record the bluesy, freight-train-styled song in 1963 during sessions for their single "From Me To You" but abandoned it after four unsatisfactory takes. They rediscovered it during the 1969 Let It Be sessions, ultimately including it on the album, where it sits shortly before closing track "Get Back". McCartney has described it as holding "great memories" of him and Lennon trying to write together, while noting George Martin may have preferred other songs over it; Lennon, meanwhile, was known for his lifelong fascination with the number nine, tied to his birth date and childhood home address.