He is the self-effacing billionaire who has played poker for a pittance in the same house for 30 years, yet gambled hundreds of millions on Anglo Irish Bank as the world was on the cusp of the worst financial crisis in recent history.
Sean Quinn may have restricted his poker losses to €5 a night but this weekend the richest man in Ireland is nursing potential investment losses of almost €1bn, coupled with the added sting of a €3.4m fine from the Financial Regulator slapped on his insurance subsidiary.
The catalyst for the change in fortunes for the Fermanagh-born entrepreneur is a massive gamble he took on Anglo Irish that has backfired in spectacular fashion.
The €715m stake in the troubled bank the Quinn family bought last summer is now worth €220m, thanks to the turmoil in the financial markets that has seen Anglo's share price tumble by 90% in a year.
That investment was part-financed by a loan from Quinn Insurances of €288m. And that loan resulted in the unprecedented fines because the company had a duty to alert the Financial Regulator before moving money from the insurance group, as insurers are required to have enough funds in place to deal with unexpected claims.
How the loan came to the attention of the regulator in the first place is unclear; the Financial Regulator will not reveal how it came to conduct the investigation that resulted in Friday's fines for Mr Quinn and his company.
The real sting, however, was in the Quinn Group's latest accounts, also published on Friday, which revealed staggering write-offs of €829m on investments last year and predicting further write-offs of €130m this year.
The write-off transformed the Quinn Group's €403m pre-tax profit to a €425m loss.
Mr Quinn resigned as director and chairman of Quinn Insurance, saying: “We will pay the fines and move on.”
Will it be that simple for the man who transformed stones from a field on the family's 23-acre farm into a fortune once worth €4bn?
Sean Quinn's risk-taking has always raised eyebrows in business circles. What marks Quinn out from billionaire contemporaries is that he doesn't just stick to what he knows: he took the fortune he made from gravel and used it to break into everything from pubs, property and plastics, to insurance and glass manufacturing.
In 1973, Mr Quinn had £200 and a corner of a 23-acre family farm in Derrylin, Co Fermanagh.
With it, he started digging out the stones stuck in a well, washed them and “footered about with lorries”.
A former captain of the Fermanagh Gaelic team, he tapped his GAA contacts north and south for customers. Sean Quinn Quarries expanded to Quinn Cement and profits started mounting. He ploughed the money into other businesses.
His empire now not only spans quarries, but building product firms and plastics factories in Europe, landfill sites, glassmaking operations, pubs and hotels, and a sprawling property empire in eastern Europe, India and Russia.
What marks Sean Quinn out from billionaire contemporaries is that he doesn't just stick to what he knows
What propelled him to the ranks of the super-wealthy was Quinn Insurances, which he reputedly set up because he was sick of paying over the odds to insure his trucks. When BUPA talked of pulling out of the Irish health insurance market last year, Quinn Direct took over in a seamless move.
For all his reputed €4.7bn fortune — now no doubt severely dented by the financial turmoil — he lives a few miles from where he was born, in Ballyconnell, west Cavan, next to the four-star Slieve Russell Hotel that is the proud centrepiece of his hotel portfolio.
His wealth sits uneasily with the sort of man his neighbours perceive him to be. He famously still plays poker with a group of older men in Ballyconnell as he has done for years, restricting the bets to 50c for 10 games so no one will lose more than a fiver.
“I don't use a mobile phone, I play cards in a house at night where you have to go out into the front street to go to the toilet,” he said in a rare public address last year.
“I enjoy that. I live a very simple life and that's the way I want to continue living that life.
“I'm not overly shy, but I much prefer to just sit back and enjoy what I'm doing, with my two dogs, the Wellington boots on, and dodging about the mountain. It gives my brain much more time to do what it's best at doing.”
Mr Quinn shared those insights in a rare public appearance at a conference in March last year — the second time he has spoken publicly in 10 years.
Displaying his characteristic loyalty to the border counties, he agreed to talk only because the conference was hosted by the Cavan County Enterprise Board. It was held, of course, at his own Slieve Russell hotel, in Ballyconnell.
“I'm not a very good speaker,” he began awkwardly. “So I'll just run through some bits of stuff that we have found handy.”
What followed was an unscripted, colloquially-delivered potted history of the Quinn Group, studded with homespun wisdom — “take it very simply” is the Quinn philosophy.
His approach to big business comes across as the business equivalent of the slow food movement. “A lot of people are rushing to phones — they're rushing to meetings backwards and forwards, and they're always in a panic, but really they're not thinking ... that's not a way to run a business,” he said.
“If there is somebody that wants me, we have secretaries and great support teams. If they can't take a call — if whoever wants me can't take a return call from me in 30 or 40 minutes — then there's something wrong. You should be slowing the whole thing down, getting the view right.”
His explanation of his knack for diversifying was similarly understated. Take the cosy anecdote he told about his move into the hospitality trade.
“Every time I used to come to Dublin, the pubs were always full, so I said to myself: ‘This has to be a simple business because they're charging a ransom for the beer, they get paid for the beer before they pay Guinness, so this seems to be a good business'.”
It wasn't all good news, though. He opened a €5m super-pub in a Berlin suburb only to shut it down because, he said, the customers would share one bottle of mineral water between them and make it last three hours.
His unpretentious ways — such as playing down his tycoon status and choosing places such as Sligo over the Bahamas for holidays — have added to his local hero status in Cavan, one of the few places he will walk down a street and be recognised.
To them, he is a local hero who has shared his riches with the communities in the border counties, when they felt overlooked in terms of government investment.
“He is a laid back type of gentleman, he has that easy way with him,” said Sean Smith, a local Fianna Fail councillor, who added that he wore his dogged ambition on his sleeve, and he was the last person on the football team who they would have marked out as a future international business tycoon.
The Quinn Group has brought Mr Quinn and his family untold wealth. It is owned by the family, which includes his wife, Patricia, a Galway woman whom he met at a dance.
They have five children, Aoife, Ciara, Sean Jr, Colette and Brenda, who are aged 18 to 31, all of whom work in the business.
Unusually for offspring of a billionaire, they rarely feature in the social pages, no doubt inheriting their father's philosophy of keeping the head down and getting on with it in the family business.