The maths world's biggest celebrity shunned its most prestigious prize on today, apparently bitter at his perceived mistreatment by fellow intellectuals.
Russian Grigory Perelman remained in his St Petersburg flat while the greatest maths minds met in Madrid for the International Mathematical Union's four-yearly congress.
The 40-year-old recluse had been due to receive a Fields Medal, known as the "Nobel Prize" of maths, after solving the Poincare Conjecture - a quandary on the properties of spheres that has bedevilled mathematicians for more than a century.
The reasons for Mr Perelman's refusal remain unclear, though press reports say he was hurt at not being re-elected a member of St Petersburg's Steklov Mathematical Institute last December.
John Ball, chair of the Fields Medal Committee, told a news conference he spent two fruitless days in St Petersburg trying to convince Mr Perelman to accept the award.
Mr Ball said his refusal "centred on his feelings of isolation from the mathematical community". "Consequently he doesn't want to be a figurehead of that community. He obviously has a different kind of psychology to other people," he said.
There was no immediate comment from Mr Perelman.
The Poincare Conjecture is so difficult the US Clay Mathematics Institute named it as one of the seven Millennium Prize Problems in 2000 and pledged a $1 million bounty to anyone who could solve one.
"They are like these huge cliff walls, with no obvious hand holds. I have no idea how to get to the top," said Terence Tao, who won a Fields Medal along with Mr Perelman and two other mathematicians.
Mr Perelman is the only person to have solved any of the Millennium Problems and his theory is on the verge of being verified as three teams come to the end of years of checks.
Whether he will accept the $1 million prize from the Clay institute is open to question, but Tao is in no doubt both prizes are deserved. "It is a fantastic achievement, the most deserving of all of us here in my opinion," said the 30-year-old Australian.
"Most of the time in mathematics you look at something that's already been done, take a problem and focus on that. But here, the sheer number of breakthroughs ... well it's amazing."