Paul McCartney Says He Feels 'Lucky' to Have Met John Lennon in Interview with Sean Ono Lennon

AP John Lennon and Paul McCartney

Paul McCartney says he feels “lucky” to have met his The Beatles bandmate John Lennon.

The musician, 78, opened up about their relationship in a special interview for BBC Radio 2 with John's youngest son Sean Ono Lennon ahead of what would have been John's 80th birthday. The full interview, titled John Lennon at 80, airs Oct. 3 and 4.

"I look back on it now like a fan," McCartney said in the interview, according to BBC. "How lucky was I to meet this strange teddy boy off the bus, who played music like I did, and we get together and boy, we complemented each other!"

Hosted by Sean, 44, the two-part documentary about his dad — who was tragically murdered outside his New York City apartment on Dec. 8, 1980 — also features memories from his elder brother, Julian Lennon, and godfather Elton John.

Courtesy Gunther/MPTV Paul McCartney and John Lennon

Apple Corps Ltd. The Beatles in the recording studio

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On the show, McCartney also premieres a previously unheard track with John, "Just Fun," which was written by the two when they were first starting out in Liverpool.

"There were a few songs that weren’t very good… you know, clearly young songwriters who don't know how to do it,” McCartney said about their schoolboy attempts to write songs together, before picking up a guitar and playing a short excerpt of the track. "Eventually, we started to write slightly better songs and then enjoyed the process of learning together so much that it really took off."

Referring to their iconic track "Let It Be," McCartney revealed that he now sees a photo taken by his late wife Linda of him writing with John as a reminder of their unique friendship, adding that it gives him "hope."

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The group split in 1970, with John and McCartney becoming estranged for years afterward.

In the interview, McCartney added that the "Imagine" singer was full of insecurities and that he used his famous gift of humor as a protective "shield" of confidence.

“Wait a minute, there’s this guy ‘John Lennon’ who’s like a genius, clever, witty, confident, and everything why would he have insecurities? Because we’re all fragile beings," McCartney said.

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Sean Ono Lennon/Instagram Sean Ono Lennon and James McCartney

Jordan Strauss/Invision/AP Sean Ono Lennon with his mother Yoko Ono

For John's children, Sean and Julian, however, the Beatle was just dad, even if they did have to deal with fans constantly flocking to their homes in England and New York.

Sean and Julian talk about their dad together for the first time and add that listening to his music is now something of a double-edged sword, with Sean describing the process of listening to his final album, Double Fantasy, as "overwhelming" because so many of his childhood memories are wrapped up with being in the recording studio.

The documentary also features an interview with Elton John.

"When I met your Dad I felt like I’d known him all my life and that’s the biggest compliment I can pay him,"John tells Sean, according to BBC.

The "Rocket Man" singer added that he biked 8 miles across London to buy a copy of Sgt. Pepper's Lonely Hearts Club Band in the 60s and later wound up on the Madison Square Garden stage in New York with John in the ex-Beatle's final show.

John Lennon At 80 will broadcast on Oct. 3 and 4 on BBC Radio 2.