If you see someone looking incredibly smug in the next few days, this could be the reason.
The winner of last week's £84.4 million (US$122.7 million) Euro Millions jackpot came forward on Sunday — but has decided to remain anonymous.
It is not even known whether they are a man, woman or a syndicate.
By choosing to keep their identity secret, the record-breaking winner is likely to avoid the pleas that inevitably flood in to those who declare their wins.
But with such an enormous sum of money suddenly coming into their lives, they might have trouble keeping the windfall quiet for long.
Their jackpot smashes the previous record for a UK winner set by Nigel Page, 43, and his girlfriend Justine Laycock, 41, from Cirencester, who won £56 million in the Euro Millions draw in February.
Friday's win will have made a single ticket holder the 789th richest person in Britain, according to the Sunday Times Rich List — on a par with pop star Robbie Williams and Rolling Stones drummer Charlie Watts.
It also makes them richer than former James Bond star Sir Sean Connery, who has £80m.
A spokesman for National Lottery operator Camelot said last night, "The lucky ticket holder(s) of this prize have taken the decision to remain anonymous and therefore no further details about this prize, or the location of where the winning ticket was purchased, will be revealed."
Mark Dampier, of financial advisors Hargreaves Lansdown, also had some advice on keeping their identity secret.
Dampier said, "The only way to keep it completely quiet would be not to give up your job, not to tell any relatives at all, and not to change your lifestyle. Parking a Ferrari outside your council house would be a giveaway."
He said they should also bank at a branch far away from their home, to avoid a cashier spilling the beans.
The five winning numbers in Friday's draw were 1, 17, 31, 43, and 47 with Lucky Star numbers 2 and 3.
Earlier this year, builder and self-confessed "white van man" Mr. Page, 43, and his estate agent partner Miss Laycock, 41, celebrated their winnings in front of TV cameras.
She said yesterday, "We are thrilled to pieces.
"The last couple of months have been amazing for us. We want to wish the new titleholders the best of luck."
The couple, who married over Easter, swiftly moved into a five-bedroom Cotswolds mansion, which included a 25-seat cinema, indoor pool, sauna and steam room, just down the road from model Liz Hurley. They shared a total jackpot of £112 million with a ticket bought in Spain.
Euro Millions is played in the UK, France, Spain, Austria, Belgium, Ireland, Portugal, Luxembourg, and Switzerland, but British winners have been particularly fortunate — six have won more than £237 million between them since the competition began.
Bolton gardener Brian Caswell collected £24.9 million in June 2009, while in November, Les Scadding and his wife Sam from South Wales and the Lucky Seven syndicate from Liverpool each banked £45.5 million.
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