On the evening of July 31, 1978, Kaoru Hasuike and his girlfriend, Yukiko Okudo, rode bikes to the summer fireworks festival at the Kashiwazaki town beach. They whisked down the winding lanes of their coastal farming village, a hundred and forty miles north of Tokyo. Then they parked their bikes and made their way past a crowd of spectators to a remote stretch of sand. As the first plumes rose in the sky, Kaoru noticed four men approaching. Cigarette in hand, one of them asked him for a light. As he reached into his pocket, the men attacked, gagging the couple, binding their hands and legs. “Keep quiet and we won’t hurt you,” one of the assailants said. Kaoru and Yukiko were thrown into separate sacks and loaded onto an inflatable raft. Peering through the sack’s netting, Kaoru saw the warm, bright lights of Kashiwazaki City fading into the background.

An hour later, he was transferred to a ship idling offshore and forced to swallow several pills: antibiotics to prevent his injuries from becoming infected, a sedative to put him to sleep, and medicine to relieve seasickness. Two nights later, he arrived in Chongjin, North Korea. Yukiko was nowhere in sight, and Kaoru’s captors told him that she had been left behind in Japan.

Kaoru, who was twenty, had fashionably shaggy hair and a ready smile. Cocky and intelligent, he was studying at Tokyo’s prestigious Chuo University. Still, like much of his generation in Japan, he wasn’t interested in politics, and knew almost nothing about Korea, North or South. Yukiko, twenty-two, the daughter of a local rice farmer, was a beautician for Kanebo, one of Japan’s leading cosmetics companies. She and Kaoru had been dating for a year, and he planned to propose to her once he finished his law degree.

The overnight train from Chongjin to Pyongyang was bumpy, and by the time Kaoru arrived the next morning he was furious. “This is a violation of human rights and international law!” he shouted. “You must return me to Japan immediately!” His abductor watched his tirade calmly. Kaoru, seeing that confrontation wasn’t getting any response, tried evoking sympathy. “You have to understand that my parents are in ill health,” he explained. Their condition would worsen if they worried about him.

“You know,” his abductor said, “if you want to die, this is a good way to do it.” He told Kaoru that the reason he had been kidnapped was to help reunify the Korean Peninsula, the sacred duty of every North Korean citizen. After all the pain his Japanese forefathers had inflicted on Korea, the man continued, it was the least that Kaoru, who had benefitted from his country’s rapacious colonial exploits, could do. Precisely how he would hasten reunification was left ambiguous. The abductor hinted that he would train Korean spies to pass as Japanese, and perhaps become a spy himself.

“You see, once the Peninsula is unified under the command of General Kim Il-sung, a beautiful new era will begin,” he went on. North Korean socialism would spread throughout Asia, including Japan. “And when that glorious day comes, we Koreans will live in peace. And when you go home at that time you’ll have an excellent position at the top of the regime!”

Kaoru was placed in an apartment in Pyongyang. Escape was virtually impossible; three minders monitored him twenty-four hours a day, each taking an eight-hour shift. Although he didn’t have a religious background, he tried praying, placing his palms together and pressing them to his eyes. This display of piety elicited ridicule from his captors. In North Korean movies, the only characters who prayed were the cowardly Japanese prisoners begging for mercy.

Kaoru was given access to a restricted library with Japanese-language books about the history of North Korea. Japan demobilized the Korean Army in 1907, and officially annexed Korea on August 29, 1910. The Japanese were careful to distinguish between Korean leaders (inept, corrupt) and the Korean people (proto-Japanese, full of potential), and predicted that Korea would thrive now that it was part of the Japanese Empire. From the late thirties through 1945, Japan pushed Koreans to assimilate, requiring them to speak Japanese, take Japanese names, and worship at Shinto shrines. Men were forced to labor in Japanese factories and mines, and some women were dragooned into sexual slavery. Roughly two hundred and thirteen thousand Koreans fought in the Japanese Imperial Army and Navy.

By the end of the Second World War, four million Koreans were living outside Korea, and more than seven hundred thousand Japanese civilians and troops were living inside Korea. But the loss of the Japanese Empire meant that a new theory of Japanese identity was required. In postwar Korea and Japan, a rhetoric of racial purity thrived. Within the Korean Peninsula, the newly independent North and South competed to see which could more thoroughly eradicate Japan’s influence, in an effort to become the Korean people’s legitimate homeland.

In January, 1980, after eighteen months in North Korea, Kaoru was summoned to his minder’s office. Several officials were waiting for him. They announced that Yukiko, his girlfriend, was in North Korea after all. In fact, she was in the next room. It turned out that the story about her being left behind in Japan had been a ruse designed to force Kaoru to cut all emotional ties to Japan. The couple had been undergoing the same pedagogical routine: learning Korean, studying the regime’s ideology, wondering whether they could survive in this strange country. Like much else in North Korea, their isolation had been staged.

Kaoru and Yukiko married three days after they were reunited. “I would have done it that morning,” Kaoru said. “I didn’t want to wait.” The groom received a haircut and was outfitted with a new white shirt and a necktie; the bride wore a simple flower-patterned dress. The ceremony was officiated by the most senior official present, who opened by invoking the blessings of the Great Leader, Kim Il-sung.

The most important wedding present a North Korean newlywed couple can receive is a home in which to start their new life. (Because there is virtually no private property, the gift is from the state, and can be withdrawn at any time.) Hasuikes’ first home was a traditional one-story cinder-block house an hour south of Pyongyang. Painted white, it had a wooden roof with ceramic tile shingles and five rooms: a kitchen, two bedrooms, a living room, and a bathroom. In the back was a small garden where Kaoru grew vegetables. He got seed and fertilizer by trading cigarettes with farmers from a nearby food coöperative, and arranged for a cow to till the field at the beginning of the growing season. He became fond of kimchi, and started making it for himself in the traditional manner, stuffing cabbage and hot red peppers into clay pots and burying them in the yard to ferment.

Their house was situated in one of the many guarded “invitation-only zones” that dot suburban Pyongyang. The area, a square mile, limited its inhabitants’ freedom while warning outsiders that only those “invited” to enter were welcome. All North Koreans develop a heightened sensitivity to coded language, and they knew well enough to avoid it. The development was a well-tended prison inside the secretive state. Still, the housing and food were better than what most North Koreans had. Kaoru saw the place as a gilded cage.