An American Beatles fan visiting Liverpool for the first time struck lucky when he bumped into Sir Paul McCartney himself while touring the star's old home city.

Retired actor Lance Mancuso was posing for a picture outside the barber's shop on Penny Lane during a day-trip to the city when the music legend walked up behind him and said, 'Hi, I'm Paul'.

Lance, 59, from Las Vegas, who had been brought to Liverpool by his British cousin Clive Langley, was over the moon and the pair exchanged greetings and shook hands.

Lance Mancuso bumped into Paul McCartney (centre together), while he was visiting Liverpool with his cousin Clive Langley. Sir Paul was there filming with James Corden (right)

The encounter was even more extraordinary considering Penny Lane shop keepers have lived and worked there for some 40 years without ever seeing the musician who put the street on the map.

The 75-year-old multi-millionaire was in his hometown filming with comedian James Corden. Looking fit and in good spirits he quickly drew a crowd of well-wishers during his unscheduled visit to the street made famous by his 1967 song.

'I was standing outside the barber's shop in Penny Lane, I looked around and there was Paul McCartney,' Clive Langley told MailOnline.

'He walked into the barber's shop and said hello to everyone in there. There were people having their hair cut and others waiting.'

Barber showing photographs! Sir Paul surprised an american Beatles fan visiting Liverpool for the first time as he posed outside the shop mentioned in the 1967 hit song

Sir Paul shook hands with US tourist Lance, 59, and thanked him for his service when he noticed he was in a military jacket

Mr Langley had brought his American cousin, Lance to visit Tony Slavin's salon, which is the 'barber's shop', mentioned in the song Penny Lane.

'We couldn't believe it. Then Paul McCartney walks out of the barber's shop and says 'Hi, I'm Paul', as if we didn't know who he was!

'One shop-keeper told us it was a million-to-one shot that we had seen Paul McCartney.

'There's a woman who runs has run a second-hand clothes shop in Penny Lane for 40 years and she said she had never seen him.

The legendary singer-song writer was in the city with chat show host James Corden (right) where the pair visited Sir Paul's childhood home - the first time he'd been there in 54 years

Retired actor Lance described Sir Paul (pictured) as 'very cool' adding he 'was very gracious and had a nice handshake'

The singer-song-writer shook hands with Lance, 59, a retired film actor from Las Vegas, and exchanged greetings.

'Paul McCartney was very charming,' Mr Langley, 61, from Leicester, explained.

'He noticed that Lance was wearing a veteran's jacket and he thanked him for serving in the armed forces.

'Lance told him that he was a big fan and that he loved his music.

'Paul McCartney was only in the street for a couple of minutes but he quickly drew a crowd. People came out of the shops around to have a look.

'James Corden was with him. They were recording something for his show, the production team explained.'

Sir Paul also visited his childhood home in the Liverpool suburb of Allerton

Sir Paul was persuaded to return to film a skit with comedian James Corden for his chat show

The 75-year-old former Beatle strolled around his former home which he last saw in 1964

Sir Paul gave an impromptu rendition of When I'm 64 in front of stunned tourists

Sir Paul moved to the three-bedroom terrace with his parents and brother Mike in 1955

The Beatles legend, who was travelling in a Grey Mercedes people carrier with blacked-out windows then led the film crew around his native city, passing by the various statues to The Beatles, before visiting his childhood home in Allerton.

Lance Mancuso added: 'Paul McCartney was very cool.

'He was very gracious and had a nice handshake. He looked like he was enjoying himself being back in Liverpool.

'I came to Liverpool to try to feel some of the Beatles magic and I met Paul McCartney himself, I couldn't believe it!'

A week earlier the retired actor and volunteer fire-fighter had bumped into the former Beatle's daughter Stella McCartney outside her fashion house in west London.