Watch new footage of John Lennon in the studio, dragging Paul McCartney

Diss tracks looked a lot different in 1971.

Here we have John Lennon performing in the studio with his fellow Beatle George Harrison and the Plastic Ono Band. The song? A funked out version of "How Do You Sleep?" from Lennon's second solo album, Imagine.

The song's lyrics take aim Paul McCartney, whose troubled relationship with Lennon led to The Beatles' break-up in 1970. "A pretty face may last a year or two / But pretty soon they'll see what you can do / The sound you make is muzak to my ears / You must have learned something in all those years," Lennon sang.

Now, almost 50 years later, the fire in Lennon's music has burned down to an ember. This footage is less about the drama than it is about a previously unseen look behind the scenes at a genius artist doing his thing. It's part of an upcoming reissue of Imagine, out on Oct. 5. Read more...

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