At the end, he performs a surprise gig to very lucky crowd in a Liverpool pub.
McCartney made it even more poignant when he told Corden: "He is".
In between songs, McCartney autographs the Penny Lane wall and visits his childhood home.
Then they pulled up at the home where he lived during his late teen years, and where he and John Lennon wrote their hit songs.
Corden labelled it "the most attractive story" he has ever heard, before the pair perform a version of it.
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Iran kept a firm head on all fronts, despite David Silva's attempted volley that sailed over the crossbar after 30 minutes. Costa, who also scored two goals in the opening match, has three goals at this year's World Cup , trailing Ronaldo by one.
McCartney also showed Corden his favorite spot in the house, the bathroom, which he calls the "acoustic chamber", because "everything sounds better in the bath", McCartney sang to Corden, while also explaining that he would spend hours with his guitar in it. "I didn't feel it coming". "So I wrote the song 'Let it Be, ' about positivity".
Carpool Karaoke was clearly Corden's breakout, but I like how he's used the segment not as a senseless gag to boost YouTube views, but as a real opportunity to get to know the guests that ride around in the auto.
As they made their way down the road, the song began to play on the radio and the former Beatle sang along before they left the auto and the singer signed his autograph on the road sign.
"If my granddad were here right now, he'd get an absolute kick out of this", Corden added, with tears still in his eyes.
Check out the Paul McCartney Carpool Karaoke video below.