This segment was originally broadcast on Jan. 28, 2007. It was updated on July 15, 2007.

Joe Dresnok could be the ultimate runaway. Growing up an orphan in Virginia, he kept running away from abusive foster homes. Then, as a soldier serving on the DMZ between North and South Korea, Dresnok did the unthinkable: in 1962, he ran through a minefield and defected into North Korea, where his unthinkable act led to an unimaginable life.

As Bob Simon reports, Dresnok has had for 44 years a mysterious isolated existence in that mysterious isolated country. No one outside North Korea has heard from Dresnok – until now.

Dresnok told his story to two British filmmakers, Dan Gordon and Nick Bonner, who have made a documentary called, "Crossing The Line." They had already made two documentaries in North Korea—one on that country's soccer team; and another on star gymnasts training for North Korea's annual spectacle called the Mass Games.

Gordon and Bonner earned the government's trust, so much so that after six years of trying they finally met Joe Dresnok.

"This is a man who disappeared off the face of the known world in 1962. And I went into this room, very sort of dark brick room. This sort of tall man in a black uniform came in. And he sat down, said, 'Hello Boy. I gather you wanna, gather you wanna talk about making a film about me.' And it would have been less surprising to have met Elvis Presley," Bonner recalls. "And yet here was this man in front of me, sat there, Joe Dresnok, who no one has seen since 1962."

Back in 1962, JFK was president and Dresnok was depressed and desperate. His wife had just divorced him, and then after leaving his base without permission for a night of womanizing, he was about to be court-martialed.

"I was fed up with my childhood, my marriage my military life, everything . I was finished. There's only one place to go," Dresnok told the filmmakers. "On August 15th, at noon in broad daylight when everybody was eating lunch, I hit the road. Yes I was afraid. Am I gonna live or die? And when I stepped into the minefield and I seen it with my own eyes, I started sweating. I crossed over, looking for my new life."

North Korean soldiers surrounded him, as portrayed in the documentary, and some wanted to kill him. Instead, Dresnok was taken by train to the capital, Pyongyang, for interrogation. He was used to running away but he had never run to a place like this before.

Much of North Korea was in ruins a decade after the war. Kim Il Sung, known as "The Great Leader," was Asia's version of Joseph Stalin. One morning, Dresnok woke up to discover that North Korea already had an American defector.

"I opened my eyes. I didn't believe myself. I shut them again. I must be dreaming. I opened them again and looked and, 'Who in the hell are you?' He says, 'I'm Abshier.' 'Abshier? I don't know no Abshier,'" Dresnok remembers.

Larry Abshier was another American soldier who had defected three months before Dresnok. Two more GIs would follow over the next two years, Jerry Parish and then Sgt. Charles Jenkins.

They were a propaganda bonanza for the north, which put them on magazine covers, looking pleased and prosperous in paradise. They broadcast their happiness in the north through loudspeakers to American troops at the border.

All were high school dropouts, who had thought more about what they were running from, than where they were going. Misfits in the Army, they were outcasts in North Korea.

"Different customs. A different ideology," Dresnok explains. "The uneasiness of the way people look at me when I walk down the street. 'Oh, there goes that American bastard.' I didn't want to stay, I didn't think I could adapt."

Four years after Dresnok defected, he and the other Americans had had enough. They sought asylum in the Soviet embassy but the Soviets handed them right back to the North Koreans.

"I think all four of them thought they'd be shot. And what's remarkable to me is that they weren't. The authorities painstakingly decided that we will convert them almost. That, you know they will come to our system," Dan Gordon says.

The filmmaker says that conversion process worked. Running away was no longer an option. So, since he couldn't get out, Dresnok vowed to fit in.

"They might be a different race. They might be a different color. But God damn it I'm gonna sit down and I'm gonna learn their way of life. I did everything I could. Learning the language. Learning the customs. Learning their greetings. Their life. Oh, I gotta think like this, I gotta act like this. I've studied their revolutionary history, their lofty virtues about the Great Leader," Dresnok recalled. "Little by little, I came to understand the Korean people.

And "the Korean people" finally accepted the Americans when they started starring in propaganda films that were big hits in the north.