This is The Beatles “The One Where Ringo Was On The Toilet”. This story from Paul McCartney himself gives an insight in to the life of recording with the Beatles.
On 31 July 1969, following two days of rehearsals and rough takes, The Beatles finally began recording Hey Jude for the album.
There is an amusing story about recording it. We were at Trident Studios in Soho, and Ringo walked out to go to the toilet and I hadn’t noticed. The toilet was only a few yards from his drum booth, but he’d gone past my back and I still thought he was in his drum booth. I started what was the actual take, and ‘Hey Jude’ goes on for hours before the drums come in and while I was doing it I suddenly felt Ringo tiptoeing past my back rather quickly, trying to get to his drums. And just as he got to his drums, boom boom boom, his timing was absolutely impeccable. So I think when those things happen, you have a little laugh and a light bulb goes off in your head and you think, This is the take! and you put a little more into it. You think, oh, fuck! This has got to be the take, what just happened was so magic! So we did that and we made a pretty good record.