Tricksters in South Korea have been arrested for selling marked playing card decks that can be read using specially designed contact lenses.
A group of three men were arrested who officials say made and sold 26,400 sets of the cards over a 12-month period.
They also sold their technology to China "for handsome sums", the Associated Free Press wrote.
The packs sold for a lot of money, according to the report, with news of them gathering in orders from the US too.
"The suspects are also accused of smuggling 2,000 pairs of specially designed contact lenses from China, with which their marked cards can be read," the report added.
The backs of the cards were marked with information printed in fluorescent pigment, so an opponent"s cards could be read during a game with the special contact lenses.
Needless to say, these contact lenses are not available to buy online from reputable companies in the UK - though other specialist lenses, such as coloured contact lenses, are.
by Alexa Kaczka