The journey from the Von Neumann to the Niemann affair has much to teach us about the changed landscape of the sport

There really is, it turns out, a true story involving cheating in chess and a vibrating crotch. Only this one is a whodunnit that dates back more than 30 years and was only solved last week.

Imagine the scene at the World Open in Philadelphia in 1993 when a mysterious unrated player with fake dreadlocks and headphones, and with a bulge that vibrates in his trousers, shows up. Now multiply it 100-fold when this unknown amateur, who calls himself John von Neumann after the founder of game theory, draws with a grandmaster, Helgi Ólafsson, in round two.

“I was sure I was playing a complete patzer,” Ólafsson said afterwards. “He had no idea about the game, and I even thought he was on drugs. He took way too much time to reply to obvious moves, and he was very strange.”

To make things even weirder, in round four Von Neumann then loses on time after only nine moves – despite having two hours for the game. Yet he still ends up winning a few hundred dollars in prize money. At which point he is asked by suspicious organisers to solve a simple chess puzzle, flees, and is never seen again.