Austin Butler was left star-struck after finding himself sitting opposite Sir Paul McCartney on a train.

Austin Butler got to meet his hero Sir Paul McCartney on a train

Austin Butler got to meet his hero Sir Paul McCartney on a train

The 'Elvis' star is a huge fan of the Beatles and had a "pinch me" moment when he hopped on a train from Paris to London with fashion designer Stella McCartney - and she brought along her famous father for the ride.

Speaking on 'The Late Late Show with James Corden', Austin explained he'd befriended Stella in London and she'd invited him to her Paris Fashion Week show before getting the train home together with her dad. He said: "She heard I was there (in Paris) and then she called me and said ''Hey I heard you are in Paris would you be able to come to my show tomorrow morning at 11 am?'

"I said ''Stella, I'm on a train heading back to London at 11 a.m. so I don't know if I can'. And she said 'Well if you can get your train moved and you come to my show at 11 then you can ride the train back with me and my dad'."

Austin agreed and took the train with Stella and her dad - and he couldn't believe he got to spend hours sitting opposite his idol as they travelled back to London.

He added: "I'm sitting across from Paul. We are talking and it's that thing where you tend to meet people that you really admire in a crowd and you can't speak for more than two seconds but with this suddenly we are locked in a train together and we just talked and he was so human. It was just amazing."

Austin revealed his favourite moment of the trip came when Stella played a song her dad had previously listened to with Elvis Presley, who is played by Austin in Baz Luhrmann's new movie.

He went on: "Suddenly, I'm sitting on a train across from Paul McCartney, the French countryside is going by and (Stella McCartney) plays the song that he (Paul) listened to with Elvis.

"And he's drumming it out on the table and singing the song to me and those are those moments where you just have to pinch yourself. I can't believe this is my life right now.And then he gave me a hug and we went our separate ways afterwards. It was so special."