Merrill Newman, 85, active retiree and intrepid traveler, preferred exotic places to popular ones. He had sailed around the world. He had been to Cuba and the Galápagos Islands. So it was not so odd when he decided that his next journey would be a return to North Korea, where 60 years ago he did top-secret work as a United States Army intelligence officer.

The Korean War still echoed within him. In early 1953, he served on the island of Chodo, advising North Korean anti-Communist guerrillas in raids on the mainland. These fighters crossed the Yellow Sea in leaky old junks. They ambushed supply trucks. They stole weapons. They rescued refugees and attacked enemy soldiers and local Communist leaders.

Mr. Newman’s wartime years were followed by a successful career, first as a high school teacher and later as an executive for high-tech companies in Silicon Valley. He seems an unlikely person to become a prisoner of war. But on Oct. 26, at the end of a 10-day guided tour, he was pulled from his flight as he was about to leave Pyongyang, the North Korean capital, and accused of war crimes.

Last week, North Korea’s state-run news agency released a video of the bespectacled octogenarian reading a stilted “apology” for his “indelible” offenses. Late Friday, that act of contrition appeared to have led to his release and a flight out. He landed in Beijing.