Sir Paul McCartney and his wife Nancy Shevell sneaked into a cinema to see 'Yesterday'.

Nancy Shevell and Paul McCartney

Nancy Shevell and Paul McCartney

The Beatles legend has admitted he was sceptical at first about the movie which stars Himesh Patel as singer/songwriter Jack Malik, who lives in a world where nobody knows that the iconic Liverpool band existed but himself, and thought it was a "terrible idea".

The 77-year-old music icon politely declined an offer to see the film at an official screening, but later asked his 59-year-old spouse if she fancied watching it at a theatre in the Hamptons in the US for a "date night".

He told Billboard: "That began when Richard Curtis, who [directed] 'Love Actually', wrote to me with the idea.

"And I thought, 'This is a terrible idea', but I couldn't tell him, so I said, 'Well, that sounds interesting - good luck.'

"I didn't think anything more of it.

"Then someone said Danny Boyle would direct it, and I thought, 'They must think they can pull it off.'

"And I thought nothing more of it until they asked if I wanted to see a screening.

"I asked Nancy, and we said, 'Let's go, you and me, on a date to the cinema.'"

The pair were only spotted by a few audience members, and they giggled their way through the flick every time McCartney's name was mentioned - but they ended up enjoying Danny Boyle's film, which also stars the likes of Lily James, Ed Sheeran and James Corden.

The 'Let It Be' hitmaker added: "We were in the Hamptons in the summer and there it was, so we got two tickets and walked in when the cinema went dark. "Only a couple of people saw us.

"We were in the back row, giggling away, especially at all the mentions of 'Paul McCartney.'

"A couple of people in front of us spotted us, but everyone else was watching the film. We loved it."