SADO ISLAND, Japan — Charles Robert Jenkins was planning a trip to America this spring to do “Larry King Live” and promote his book, but the tourist season on Sado Island is heating up.

So Mr. Jenkins decided to stay home, sell cookies, and sign autographs. At 68, the former U.S. Army sergeant who defected to North Korea and lived as a captive in the curtained-off communist state for 40 years is a celebrity in Japan.

His Stalinist odyssey — marriage to a Japanese woman who was abducted by North Korea and given to him one evening, her highly publicized release, and their eventual reunion — is household knowledge in this country. An impish man with a thick North Carolina drawl, he has done as many as 28 interviews in one day with Japanese press and broadcast outlets. His autobiography, being published in America this spring as “The Reluctant Communist,” has sold more than 300,000 copies in hardback in Japan.

“Everyone in Japan knows who I am,” he said.

At age 24, while serving in South Korea, Mr. Jenkins drank 10 beers and stumbled northward across the world’s most heavily militarized border. He surrendered his M-14 rifle to startled soldiers in North Korea.

“I was so ignorant,” he recalled. He had deserted the Army for what became a self-imposed life sentence in a “giant, demented prison.”

There, over the next four decades, he acted in propaganda movies and raised chickens. He taught English, made the Korean food staple kimchi, and memorized the teachings of President Kim Il Sung.

After 15 years, his keepers delivered a lovely Japanese woman to his house and urged him to rape her. She had been kidnapped from Japan. Mr. Jenkins was gentle with her, she came to love him, and they were married. They had two daughters who were in training to become multilingual Stalinist spies — when something happened that was truly nutty.

North Korea let them go. His wife got out in 2002, he and his daughters in 2004.

Trading on his celebrity, Mr. Jenkins now works as a glad-hander in the gift shop of a museum here on Sado Island.

Located off the west coast of Japan, Sado is a green, isolated isle of rice paddies and tall mountains. Historically, it is Japan’s Elba.

Sado is now a minor tourist destination — and Mr. Jenkins has become one of its major attractions.

He sells sugar cookies seven hours a day, six days a week, shaking hands and posing for pictures with tourists.

His wife, Hitomi Soga, who is 20 years younger than Mr. Jenkins, grew up here on Sado and now works at city hall.

It was on this island on August 12, 1978, when Ms. Soga was 18 years old, that three North Korean agents grabbed her at dusk, stuffed her in a black body bag and stole her away on a ship.

Fifteen years later, North Korean leader Kim Jong Il admitted that his agents had abducted 13 Japanese, including Ms. Soga.

It is almost impossible to overstate the emotional power and political sensitivity of the abductee issue in Japan. The government bans all imports from North Korea, refuses to give it food aid, and forbids its ships to enter Japanese harbors. More than any other country, Japan has been talking tough in six-nation negotiations meant to coax North Korea into abandoning nuclear weapons.

The national obsession with abduction has made Ms. Soga famous as well. But she does not talk to the press.

Ms. Soga is not pleased that her American husband does talk, and talk and talk. Mr. Jenkins said that over the past four years, she has warned him not to write an autobiography, not to grant interviews, and not to put his signature on the cookie boxes he sells.

She is now warning him, he said, not to write a second volume of his life’s story.

“She said that, in the end, North Korea is going to get fed up. I am going to walk out my garage one morning to walk the dog, and I am going to get a bullet in the head. Very possible.”

When he learned the arc of Mr. Jenkins’s life inside North Korea, Jim Frederick, a senior editor at Time magazine who helped write “The Reluctant Communist,” was disappointed.

Mr. Frederick writes in the book’s foreword: “I thought it would have been ideal if he had lived a life of decadent privilege at the right hand of Kim Jong Il, if he had acted as a kind of court jester in the Dear Leader’s inner circle.”

But Mr. Jenkins had no such privilege, no such access. He is not a court jester. He is not a shrewd political observer. By his own description, he is an ill-educated guy who walked the wrong way.

He grew up in a large, poor family in the small, poor town of Rich Square, N.C. He did poorly in school and joined the National Guard at 15 after lying about his age.

Soon, he joined the Army and was sent off to South Korea to prowl around as leader of a “killer hunter team” along the DMZ, the stupendously well-guarded border between the two Koreas. While there in 1965, he grew unhappy with his dangerous job. He also had heard rumors that he was soon to be sent to Vietnam.

“I gave in to the worst side of myself,” he says in the book. “I attempted to run from all of my problems rather than confront them head-on like a man and a soldier.”

He walked into North Korea at night, stupidly assuming that because it was a communist country, it would turn him over to the Soviet Union, which would turn him over to the American government.

Instead, he became a Cold War trophy who outlasted the Cold War, a semi-privileged captive in a country that, with each passing decade, grew poorer, more isolated, more paranoid, and more threatening to the world.

Mr. Jenkins makes no attempt in his book to explain why this happened. He doesn’t have a clue.

The power of his story is in the details of his life. It was unspeakably boring, as well as depressing, drunken, hungry, cold, maddening, and painful.

Speaking of pain: One warm summer day, while teaching English in a military school, Mr. Jenkins showed up for work in short sleeves. A “US Army” tattoo was visible on his left forearm. This upset the Communist Party cadre there.

Doctors were called in to cut off the tattoo, without the benefit of anesthetics.

It should be noted that Mr. Jenkins is the only source for this and nearly all the other stories he tells about his life in North Korea. He does, though, have a wicked scar on his left forearm.

There were three other American deserters in North Korea. For years they lived miserably together. In the early 1970s, their minders gave them each a female cook.

They were divorced, infertile North Korean women who spied on the Americans and were under orders to have sex with them.

The first woman selected for Mr. Jenkins hated him. “I am not cooking for any American dog,” she told him. A U.S. soldier had killed her father in the Korean War.

Mr. Jenkins recalled that he did not particularly want to have sex with this woman twice a month, as his minders said was required. Mr. Jenkins told them “to go to hell” and stay out of his private life.

As punishment, his hands were tied behind his back and he was repeatedly punched in the face — by one of the other American soldiers.

Thanks to his Caucasian face, Mr. Jenkins was drafted to become an actor in propaganda films. He played the captain of an American aircraft carrier in a film glorifying North Korea’s capture in 1968 of the USS Pueblo, a Navy spy ship.

Mr. Jenkins devoted the bulk of his time, though, to survival — an endless grind of shoveling coal for heat, scrounging for food, hauling water, and standing guard at night so hungry, marauding soldiers wouldn’t steal his peaches, his corn, his chickens, or his kimchi.

The beginning of the end came when Japanese Prime Minister Koizumi visited North Korea in 2002, and Kim Jong Il unexpectedly said he was sorry for stealing away Japanese people. Soon, Mr. Jenkins’s wife was on a plane back to Japan.

She had been, he said, the rock that kept him alive, healthy, and reasonably sober in North Korea. When she flew off, Jenkins began guzzling Chinese ginseng liquor, which was 80 proof and cost $2.50 for a five-liter jug. He spent the better part of a year passed out on the floor of his house.

During that lost year, he convinced himself that Japan was holding his wife against her will. The Japanese government, meanwhile, was leaning on North Korea to release Mr. Jenkins and his daughters.

Mr. Koizumi returned to North Korea in 2004 and met personally with Mr. Jenkins and his daughters, asking them to come back with him on his airplane. The prime minister handed Mr. Jenkins a handwritten note that said the premier would “do the utmost that you can live together happily with Mrs. Jenkins in Japan.”

Still, Jenkins declined, fearing that North Korea would not let him go. He also worried that, if he were allowed to leave, he would be punished harshly for desertion by the American government and sent to jail for many years.

Finally, a compromise was reached. Mr. Jenkins and his daughters traveled to Indonesia, where they were reunited with Ms. Soga. Within minutes, she persuaded Mr. Jenkins to come home.

After a stint in a Japanese hospital, where doctors sorted out a prostate operation that had been bungled in North Korea, Jenkins put on a uniform and surrendered to American authorities. He was, he said, the longest missing deserter ever to return to the U.S. Army. (Back in North Korea, one American deserter is still believed to be alive; two others are dead.)

Mr. Jenkins faced a court-martial for desertion, aiding the enemy, soliciting others to desert, and encouraging disloyalty. But the Army was lenient with him, sentencing him to 30 days in the brig. He got out five days early for good behavior.