SOUTH KOREA – The smile was the lure. Mr Nalla Kim, a South Korean computer programmer, noticed the joyful expressions in the social media post of a fellow programmer whom he had never seen smiling at work.

Curious, Mr Kim asked his colleague what had made him so visibly happy. The answer: swing dancing.

Mr Kim had never heard of the dance form, which was created by Black Americans in the 1920s and 1930s. He discovered it when he was coming of age in Seoul in the early 2000s.

He got hooked. He started attending swing dance events in the United States and after a few years entered international competitions. He travelled to dance, but he did not have to. In the past two decades, the swing dance scene in his home town has grown into the largest in the world.

For a vintage American cultural practice to spread overseas and thrive there more robustly than at home is a story at least as old as jazz. Not in every case, though, does the transplanted form evolve into a local variant. That is what has happened in South Korea.

In Seoul these days, there are around 10 clubs dedicated full time to swing and its core partnering form, Lindy Hop.

Mr Andante Jang and his fellow K-Swing Wave dancers rehearsing at the Korean Cultural Center in New York.

PHOTO: YE FAN/NYTIMES

“In New York, where Lindy Hop was born, we have zero,” said Mr Caleb Teicher, a prominent American Lindy Hop and tap dancer.

Those Seoul clubs are filled with dancers of high skill. “I’ve heard it joked among the New York dancers who’ve gone there that a bad dancer in Korea is a great dancer in New York,” he said.

Moreover, in the jazz tradition that artists honour by developing their own voices and style, South Korean dancers have worked out their own fresh approaches to the form. “When I go there to teach, I feel like I’m their student now,” he said.

Wanting to display these developments to New York City, Mr Teicher has organised a mini-festival. On July 19, K-Swing Wave, a group of eight all-star South Korean swing dancers, are performing a free show at Lincoln Center’s Summer for the City.

The next day, the group will appear at the Korean Cultural Center New York and at a swing dance party at 92NY, the 92nd Street Y.

Mr Kim, K-Swing Wave’s project director, said the dancers selected were “the best of the best”, most of them leaders of their own groups.

Mr Andy Seo, the group’s artistic director, added that everyone had been so busy dancing, teaching and performing that they seldom had opportunities to collaborate. This is their first chance to figure out what an extended production of Korean swing dance might look like.

Like Mr Kim, Mr Seo discovered swing dancing in the early 2000s. The swing dance revival of the 1980s and 1990s in the United States and Sweden had arrived in Seoul in 1999, imported by Korean-American dancer Alex Nah.

K-Swing Wave dancers rehearsing at the Korean Cultural Center in New York.

PHOTO: YE FAN/NYTIMES

“Couple dancing was not that familiar in Korea,” said Mr Seo, who had belonged to clubs for street and K-pop dance. “But I fell in love with dancing with others.”

Mr Nathan Bugh, one of Mr Teicher’s colleagues in the popular production Sw!ng Out, recalled how a Korean couple memorised and performed the improvised social dancing of an American duo (preserved on video) exactly, including the mistakes.

At social dance occasions, Mr Bugh added, rather than following the normal practice of pairing off, South Korean dancers would either stand and watch or wait in line to have the foreign instructor as a partner, sometimes bringing cups of water so the teacher would not have to take a break.

“It was like a factory,” he said.

But every time these Americans returned to South Korea, they noticed changes.

(From left) Mr Andy Seo and Mr Nalla Kim at the Korean Cultural Center in New York.

PHOTO: YE FAN/NYTIMES

For Authentic Jazz Weekend, an annual event that Mr Kim and Mr Seo founded in 2013, the South Korean dancers invited foreign instructors – often found on the internet – who were specialists in areas in which the South Koreans felt they were weak, especially solo jazz dancing and improvisation.

At the same time, they were discovering their strengths. “Maybe it’s a cultural thing,” Mr Kim said, “but Korean dancers are really great at group formations.”

Numbers created by Mr Seo – whom Mr Bugh called his favourite vernacular jazz dance choreographer in the world – have the kaleidoscopic complexity, sharp synchronicity and clever details of the most intricate K-pop routines, while remaining recognisably in a jazz dance idiom. On multiple scales, they swing. Broadway producers should take note.

“The first piece by Andy I saw was made for students,” Mr Teicher said. “And when you looked at the dancers individually, they were not the strongest. But the choreography – it was genius. I had never seen a team jazz piece that good before.”

Mr Kim has made a project of interviewing international swing dancers about the history of the dance and their experiences, and then translating the videos into Korean.

Talking with African-American dancers, he said, he was surprised to discover commonalities. Swing dance was born from the blues of oppression, and Korea also had colonisation and caste, he said.

“Many Korean art forms are from that sadness, even if they look as happy as the Lindy Hop.

“Dance is such a great way to learn about other cultures,” he added, sharing the hope that K-Swing Wave will contribute to a two-way exchange.

Mr Seo agreed, but he stressed something simpler about swing dancing and why it should spread everywhere: It makes people smile. NYTIMES

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