The stunt, known as 'Smash and Stab', has become famous in the magic world after Barry successfully performed the trick on a number of celebrities, including Rachel Hunter and Elijah Wood. Speaking to the Sunday Tribune, Barry said he has recently become aware that a number of well-known UK magicians have injured themselves and others while trying to reproduce the trick.

"Magicians copy each others ideas all the time . . . there's no way to stop it, " he said. "But obviously, with a trick like this one, you have to know how to do it. They think they know, but they don't . . . with very bloody consequences actually."

The 'Smash and Stab' trick, as performed by Barry, involves a hidden nail under one of four polystyrene cups. Barry blindfolds himself and has the cups mixed up so that it seems neither he nor the spectator could know where the nail is. Then, still blindfolded, Barry takes the hand of the spectator and asks them to choose three of the cups. They do, and he forces their hand down on each. When the trick is performed . . . successfully . . . the block with the nail is the one left over.

"One of the UK magicians who tried to do it actually used a spectator and pushed her hand straight onto the nail, " said Barry. "Another guy really hurt his own hand. There are actually a few videos of the trick going wrong on the internet at the moment. It's pretty gory."

Barry said that the trick is now being sold in one of the biggest magic shops in New York, Fantasma, and that magicians demonstrating the trick in the store have also injured themselves. "Just this week I heard that two of them managed to stab their own hands, " he said. "I don't know if they've even set an age limit on who can buy the trick or anything like that."

Of the other tricks performed by the Irish magician, Barry said he would probably be most worried to see anyone trying to copy a famous stunt in which he hangs himself. "I mean, you could decapitate yourself if you didn't know what you were doing, " he said. "I know everything there is to know about hanging and I would advise anyone not to attempt it unless they knew exactly what they were doing."

Even with years of successful magic behind him, Barry said he still gets nervous every time he performs a dangerous trick. "The day I'm not nervous is the day I'll stop, " he said. "I have had minor injuries in the past. There was one trick that I was performing on the Jimmy Kimmel Show in the States, where I was going to push a black-eyed-pea into my ear, squeeze it along the side of my face, and take it out of my eye socket.

But the pea went all the way down my ear canal.

I could feel it moving by itself. It stopped at my eardrum. So I went home, took out the Hoover, and tried to suck it back out. That didn't work.

I ended up having to go to hospital, where they managed to get it out with a syringe in the end."