Terry O'Neill was filling in time when he took the picture that changed the course of his career.
A 20-year-old Londoner with dreams of becoming a jazz drummer, Mr O'Neill signed up in the early 1960s to work for BOAC, a precursor to British Airways, for the chance to play on both sides of the Atlantic.
But he had just missed an air steward training session, so he took a job in the airline's photographic unit to fill in the three-month wait for the next slot.
"I went to the airport and I took a picture one day, one Saturday, of a guy in a pinstripe suit surrounded by Africans in all their tribal robes. He was asleep."
Mr O'Neill had no idea who the sleeping man in the suit was but a reporter at the airport recognised him as Rab Butler, the UK's foreign secretary at the time.
"[The reporter] said my editor would like to see the film, so I gave him the film and I rang the guy at 5 o'clock or 6 o'clock and he said I love your work on these pictures. I want you to work for me at the airport every Saturday.
"Suddenly I had a job and I said but I don't really know what I'm doing. He said just do what you are doing now. Take pictures."
Another photographer, the "local hotshot", discovered Mr O'Neill and asked him to cover his shift at the airport when he was doing other jobs. A couple of months into the arrangement, the photographer died in a plane crash. Mr O'Neill was offered his job on the Daily Sketch, a tabloid newspaper.
It wanted pictures of emerging pop stars at the time based on a hunch they were going to be big. "He said there's this group which has just made a record called Please Please Me. I go down there and got one of the first shots of The Beatles as The Beatles."
It took three months to publish, but when it finally ran, the paper sold out straight away.
From there, he stumbled onto scoop after scoop. He was the right age; it was the right time; and he knew the right people, says Mr O'Neill.
"I used to go to this club called the Ad Lib Club, where all the in crowd went and we used to sit there and talk about what job we were going to get when all this was over.
"Ringo wanted to be a hairdresser. He wanted to own a chain of hairdressers. George wanted to work in a tailor's shop. It was so funny. We used to laugh about Mick Jagger singing at 40 like he'd be an old granddad."
He left the Daily Sketch when he was 24, having covered a funeral of youngsters who were murdered in a stabbing. "I went back and said: 'Listen, I can't do this any more'."
His editor, a "sergeant major" type, told him that the paper had made him and he would be finished the minute he walked out of the door.
He was wrong. Mr O'Neill went on to photograph stars including Clint Eastwood, Paul Newman, Steve McQueen and Brigitte Bardot, some of whom star in an exhibition of his work currently on at The One Fusion in Al Quoz in Dubai. The photos on show range in price from Dh10,995 (US$2,993) to Dh64,995
One of the pictures, a photograph of Faye Dunaway, whom he was married to for a time, shows the actress sitting by a pool in Los Angeles the morning after her Oscar win in 1976. "That's when they realise that their lives are going to change. It's the next day when the penny drops that their money is going to go from, say, half a million to five or six million."
Part of his success, he says, was because of the switch of major films being produced in America to Europe in the late 1960s and early 1970s.
"That's the way I got to meet all these people," he says.
"I'm the luckiest person going."