As a Brit on holiday in Las Vegas, Carl Kelly might be forgiven for daydreaming about a role in a blockbuster opposite Gwyneth Paltrow. However, the salesman from Knebworth, Hertfordshire, decided to make his dream a reality.

With no acting experience, the 29-year-old bluffed his way on to the set of Iron Man, the latest Marvel comic action film, while he was staying in Las Vegas last June.

He convinced security guards that he was an extra, and after seven hours' sitting in the background in a casino scene he was asked to film a short scene with Ms Paltrow.

"Some 38 takes later, I think they were getting pretty fed up with me – but that's what happens when you let an untrained nobody into your film," Mr Kelly said. By the end of the 10-hour film shoot, he had missed his flight home.

Mr Kelly's debut in Iron Man can be seen in multiplexes across the UK from May.