Sir Paul McCartney didn't want to go inside his old house for 'Carpool Karaoke' because it felt "weird".
The Beatles legend showed James Corden the area where he'd grown up in Liverpool for an extended version of the popular segment in 2018 and though the pair visited his teenage home on Forthlin Road - which was where he and the late John Lennon co-wrote 'She Loves You' and is now a National Trust site - in the clip, the memorable moment almost didn't happen.
James explained that, shortly before setting off, the 77-year-old musician had admitted he didn't want to go in the house.
The presenter recalled: "He said, 'I haven't been there since I left, when I was 20. I just feel weird about it.'
"I went, 'Paul, your only job today is to have a great time. So, if there is anything that makes you feel uncomfortable, we're not going to do it.' "
But James urged the 'Yesterday' hitmaker not to rule it out and they agreed when they pulled up, Paul would give him a look if he wanted to leave - prompting panic from the host.
He added to the New Yorker: "When we pulled up outside, I thought, 'Oh, man, I wish we'd devised a code word instead, because what if he's giving me the look?' "
They sat in the car together and James eventually asked if they should go in and his guest agreed, giving him a tour of the property and playing 'When I'm 64' on an old upright piano.
The segment ended when the veteran musician surprised just 50 locals at the nearby Philharmonic pub with a short set.