Way back in October 1983, a young Hong Kong broker was working one Saturday when his boss rushed through, yelling at everyone to buy Hong Kong dollars. Within hours, the authorities pegged the currency to the US dollar at a tidy profit for those local currency holders.
Then and since, Hong Kong dollar weakness has typically been related to fears about its relations with China. But now the currency is nearing its weakest point in a decade. And for once, the city's future is not the reason.
The Hong Kong dollar slide is really a side effect of years of worldwide easy money. The territory is in the unique position of having monetary policy pegged to the US and its future prospects tied to China.
Over the past decade, those two factors have produced a massive boom and several bubbles. Hong Kong's position as the world's most expensive property market, where car parks sell for $3 billion, is just one example.
Now with China slowing and the US raising rates, this, in theory, should have trapped the city between a rock and a hard place. But that hasn't happened because so much money is still available that its banks haven't needed to follow the Hong Kong Monetary Authority in tracking US rate rises.
On Monday, the gap between three-month money in the US and its Hong Kong equivalent hit the widest point since the aftermath of Lehman Brothers collapse in 2008. Also on Monday, the US dollar traded above $7.82 Hong Kong for only the third time in 10 years.
The question now is how the HKMA will manage its defence of the peg if the currency nears the weaker edge of its permitted range between $7.75 and $7.85. With $400 billion US in reserves, it has the funds available. And few, if any, expect a breaking of the peg.
The HKMA does not even have to wait until the limit is breached to sell dollars. And it might do so soon if it feels that will help ease market jitters.
But the real problem here is those markets themselves, years of easy money risk having bred complacency. The weak side of the peg has not been tested since 2005, either. Back in 1983, Hong Kong's traders were used to uncertainty and expensive money. Those today are not. But they might want to think about what that looks like.