TOKYO — At first sight, the wristwatch looks rather ordinary: a minimalist white dial with a date window, silver hands and hour markers, on a simple silver-colored metal bracelet.

It resembles a Seiko, except for an important detail: Printed on its face in black lettering, in both Hangul characters and the Roman alphabet, are the words “Moranbong” (the brand name) and “Pyongyang, North Korea.”

Made in the Democratic People’s Republic of Korea — likely in the 1970s and ’80s, although no one seems really sure about the dates — the Moranbong is one of the watch universe’s mysteries.

And, intrigued, I have spent lots of time this year searching online watch forums and old publications, and talking with the handful of people I could find who knew about the watch — although several of them refused to be identified, worried that they might be turned away during future visits to the notoriously secretive country.

It’s been quite an odyssey.

I discovered the Moranbong in February, when, just out of idle curiosity, I searched “North Korea watches” on Google, and some fuzzy images of the timepiece led me to a few — a very few — forum posts.

Then later that month on one of my regular Saturday strolls with my toddler, I stopped by my local watch shop, L o’clock, a stylish boutique that specializes in repairs and sells vintage watches from the 1960s and ‘70s. I had intended just to say hello to staff members and look at the latest offerings — but the owner, Naoto Akiyama, told me that he had been servicing a North Korean watch.

There it was, a Moranbong.

Mr. Akiyama put me in touch with the watch’s owner, who agreed to talk but only if I would not name him in this article, because of the confidential nature of his job. A few days later, on a chilly winter evening, we met at the shop after the last customers had left.

The Tokyo resident, whose collectibles range from North Korean military badges to an old Japanese Imperial Army watch, said he wanted a Moranbong so he began checking the Japanese version of the online auction platform Yahoo! Auctions daily until he saw one. He said he thought it initially would not have sold for more than about 6,000 yen ($55) — he paid 80,000 yen — although, he added, “the watch quality is good and it tells time accurately.”

Mr. Akiyama, who had gotten a closer look at the Moranbong’s mechanical movement while he was servicing it, said it was the first time he had ever seen such a movement.

He opened the watch again that evening so both its owner and I could see inside. “It looks like a copy of a rare Swiss movement, the Sonceboz Caliber ES 95 17 jewels, which was produced in the 1970s and ‘80s,” Mr. Akiyama said. “As for the exterior, the crystal covering the face is actually plastic, and is engraved with some lines as a design, which is quite unusual.”

Now I was really curious, so I started trying in earnest to trace the watch’s history.

Moranbong means “peony hill” in Korean. I have never found any explanation of why that is the watch’s name, but it also is the name of a famous park in the heart of Pyongyang, and the site of important monuments like the Kim Il-sung Stadium and the Arch of Triumph. It actually seems to be used in North Korea for a lot of things, like the Moranbong band, an all-female musical act that has been called the country’s version of the Spice Girls — and whose members were selected personally by Kim Jong-un, the country’s supreme leader.

A Google search of the words “Moranbong” and “factory” turned up the 2004 book “Under the Loving Care of the Fatherly Leader,” by Bradley K. Martin, a journalist who covered news in Asia for publications like The Baltimore Sun and Bloomberg News. The book has just one short paragraph on the Moranbong, in a chapter about corruption in North Korea: “Kang Myong-do, a North Korean trading company vice-president, told a South Korean magazine interviewer: ‘The country is in such a state, and officials are just taking money for themselves. Moranbong watch factory was built in 1978 with Swiss factory components, but it’s crummy stuff. The person who arranged it got a kickback from the Swiss for paying a lot of money for old machinery.’”

Later, another Moranbong owner told me to visit the archives of the National Diet Library in Tokyo to see a June 1985 issue of Korean Pictorial magazine, a Japanese-language publication once affiliated with Chongryon, an organization of Koreans living in Japan. (The last issue in the library is dated Winter 1997.)

The photographs of the Moranbong factory in the four-page article looked as though they were taken during World War II, not the 1980s. And it was not just the quality of the prints: black and white images that look overexposed. The pictures showed fresh-faced female employees, their hair covered with kerchiefs, standing about on the factory floor and working on the last stages of the watch assembling process at a long row of desks. Only women were depicted; their plain clothing could have been produced at any time since the 1930s as it really had no identifying style. There also was a product shot of six timepieces, with dials that appeared to be in different colors.

The text said nothing about the watch, and actually very little about the factory. But it did place the factory in Pyongsong, a town about 15 miles north of the capital that was formally established in 1969, and said the municipality was meant to be a hub for more than 30 kinds of light manufacturing, producing more than 700 products including artificial leather and rubber products. In recent years, according to French news reports, the town has become the site of a training school for nuclear scientists.

In April, while I was in Seoul to do some interviews, I visited “Clock Alley,” the local nickname of Yeji-dong, a passage in the city center lined with watchmakers’ workrooms and sales stalls.

The area had its heyday in the 1970s and 1980s, and many of the vendors from that time are still manning their stalls today. But, despite the fact that the border with North Korea is only about 30 miles away, I could not find anyone who had even heard of the timepiece, never mind being familiar with it.

My Japanese interpreter, who had been helping me search for information on the Moranbong, produced a knowledgeable source when he asked some of his academic contacts for help. Tomohiko Kawaguchi, an associate professor at the College of International Relations at Nihon University in Tokyo, owns three Moranbong watches that he bought in 2016 at an antique market in China.

Mr. Kawaguchi said that he doubts the Moranbong was ever officially exported to Japan or to South Korea (“Especially in the 1970s and 1980s, the anti-communism sentiment in South Korea was strong”).

But, “North Korea could have exported the watch to socialist or communist nations, including China,” he said. “You can sometimes find the Moranbong watches on Chinese online antique markets. Many of sellers are from the northeast region of China, which is adjacent to North Korea.”

The next source I found had similar opinions. One hot summer day, I was talking with some secondhand watch sellers in Tokyo’s lively open-air market street of Ameya-Yokocho (or just Ameyoko for locals). None of them had seen a Moranbong for some time — although at least they knew what it was — and one directed me to a pawnshop a few streets away.

Its owner (wearing a fascinating watch-shaped bolo tie) called a friend, who arrived an hour later with a large messenger bag. He was willing to talk about his Moranbong, but also wanted to remain anonymous because he travels to North Korea often and was concerned about how authorities might react to an interview.

Over coffee, he told me he had never seen anyone in North Korea wearing a Moranbong and doubted that it even was sold there.

(He did, however, pull from his messenger bag an Omega, one of the many custom timepieces that the North Korean government has commissioned occasionally over the past 50 years or so for special occasions or to give to visiting dignitaries. This one, for example, was ordered to commemorate the 70th birthday of Kim Il-sung, who led the country from its founding in 1948 until his death in 1994. His grandson, Kim Jong-un, has maintained the tradition — although he is often seen wearing a Movado watch, an American brand whose Swiss origins are reflected in its designs.)

In September, when I thought I had exhausted the subject — and that the Moranbong would continue to be just one more interesting and elusive bit of horological trivia, I got a message from Mr. Kawaguchi. He had just returned to Tokyo after a visit to North Korea.

While in Pyongyang, he said, he saw a new Moranbong watch in a souvenir shop for visitors. But this time, it was a quartz model and priced at 5,500 Japanese yen.

“On the box of the quartz watch, the name of the trade company, Sinheung, was printed,” he said. “I think that the name Moranbong still exists as watch brand, but I’m not sure if there is still an operating factory which makes mechanical watch.”

So perhaps my search is not finished after all.

Kantaro Suzuki contributed reporting.