Netflix's global hit drama features striking outfits, including the green tracksuits and pink jumpsuits worn by the main characters.
Now there's huge demand for copies, and that's giving a boost to South Korean clothing makers.
Kim Jin-Ja owns one garment factory:
"October is usually a slow month for the sewing industry, but thanks to 'Squid Game' and Halloween we are stitching as fast as we can, even though we started taking orders pretty late compared to others. We are sewing 6,000 tracksuits. Thanks to 'Squid Game' and Halloween, we're super busy right now."
The sudden demand is very welcome.
Kim says her sales plummeted to a third of normal levels during the global health crisis.
And the country's garment trade had been in decline anyway, as high wages make it hard to compete with China, Vietnam and Indonesia.
Now producers hope demand for goods with a 'Made in Korea' label will help boost exports.
In a Seoul market, 'Squid Game' tracksuits sell for about $25.
Vendors say they can't get enough costumes to meet demand.
Some also say they recognise themselves in the cash-strapped characters featured in the hit show.
'Squid Game' has been watched by 142 million households since its debut in September.
That's helped Netflix add more than 4 million new subscribers.