Daniel Radcliffe has admitted he cannot use the Tube - and that he got caught out when he had to film scenes for a Harry Potter movie on London Underground.
The star, 21, who has a home in London, does not dare get on the Tube for fear of being mobbed by fans.
He told the Radio Times: "I don't take the Tube, because it can go a bit nuts, and if it goes nuts in a small space that can be a bit weird - so I don't know how to use an Oyster card.
"In Harry Potter And The Order Of The Phoenix there's a shot of me and Mark Williams (Mr Weasley) going through the gates at a Tube station and I try to put my Oyster card through the machine like it's a ticket, rather than swiping it."
Daniel, worth an estimated £48 million thanks to his role as the teen wizard, said his mistake was not edited out of the movie.
"It's in the film! It makes total sense because of the character of Harry, but that was really by fluke," he said. "So I'm more likely to get tripped up by something like that, which to everybody else is totally normal."
The actor said of his future: "I'm never going to be as famous as I am today. Or as I was a few years ago. That's all going to go away, and I'll be able to just get on with being an actor."
Top acting talent has appeared in the Potter films over the years.
But Rupert Grint, who plays Ron Weasley, used to think of his veteran co-stars as "old people".
He told the magazine: "It's only in the last couple of years that I've realised how amazing the cast is."