Sir Paul then climbed into the passenger seat and the pair broke into a version of The Beatles' classic Drive My Car. During the party, McCartney sat down at the piano and played a new song to the delight of everyone in attendance.
Sir Paul then took Corden to The Philharmonic pub in Liverpool city centre, where drinkers were treated to a surprise gig. "Can you please, please help me?"
Corden responded, "That's the most handsome story I've ever heard", and then the two sang the song together.
Paul directed James to the road he immortalized in song, Penny Lane, whose famous sign they autographed.More news: Trae Young: 'I want to do something that has never been done'
When the 18-time Grammy victor explained to Corden that The Beatles' "Let It Be" was inspired by a dream he had about his mother, the late-night host started tearing up.
After teasing the first song he ever wrote, the rather catchy "I Lost My Little Girl", McCartney set course for a trip down memory lane - as well as the actual Penny Lane, which they completed with a rendition of "Penny Lane".
As Corden brings The Late Late Show to United Kingdom shores, the presenter and actor enlisted the nation's ultimate music export Paul McCartney for a sing-along in the passenger seat. "I didn't see that one coming around the corner", he said.
Corden replied, "That's the most handsome story I've ever heard". "She gave me the positive word".
"I've never been in since I lived there", Sir Paul says. "And I remember them playing that. My dad would be in there (the next room) watching telly, we'd be in here, and we'd just written She Loves You, which was a big Beatles hit".