This is what happened when a practical joker filmed himself approaching shoppers, accusing them of stealing.
Sanaan Akhter posed as a security guard clad in sunglasses and a suit.
He told one customer: “I’ll let you off if you do star jumps” and convinced another customer to leave TopShop after telling him he was not allowed to eat in the branch.
“It was all banter at the end of the day,” he said.
“I was amazed at the level of compliance.
“It is a good sign I suppose that people are compliant, they look up to authority.
“People see a badge or uniform and they respect that. There is a lot of obedience.”
Last month Sanaan, who will begin an optometry course at Cardiff University in September, posed as a sheik and tried to buy the entire Apple store and a £6m watch from a jewellery shop.
Watch the Fake Arab Prince when he went shopping in Cardiff
“I don’t want to be a one trick pony,” he said.
“I have a whole host of ideas I want to put on tape but it is quite hard,” he said.
“We have been into a few stores to see what we can get done.
“It is all about putting Cardiff on the map.”