North Korea, says journalist Melanie Kirkpatrick in her new, well researched book "Escape From North Korea" (Encounter books, 350 pages, $25.99), is the world's last closed totalitarian state.

Foreigners and foreign goods are kept out; citizens may not leave. If they are caught, they are executed or sent to a gulag. If they make it to South Korea, Thailand, Cambodia or the United States, their left-behind relatives will be punished similarly. Since the first modern wave of refugees fled during the famine of the early 1990s, only 128 have made it to U.S. soil. Since the end of the Korean war in 1953, only 25,000 North Koreans have escaped at all.

North Korea keeps its citizens in the dark ages, not only metaphorically, but also physically. The country is "so short of electricity that much of the country is switched off in the early evening," Kirkpatrick writes. The dictators have successfully kept modern information technology away from all but a few high-level elites.

North Korea "is locked in a time warp. It is Ground Hogs Day 1953 over and over again."

Escape requires money and courage, and the help of an underground railroad modeled after the one that helped slaves escape from the American South. Since it is too dangerous to organize on a centralized scale, it is run by individuals, mostly Christian missionaries forced to work with mercenary and unreliable brokers who ferry North Koreans by car, railroad and on foot into China and then to a third country, usually South Korea.

Women refugees often fare badly; if caught in China, or tricked by unscrupulous traffickers, they are often married forcibly to Chinese men. (The one-child policy has resulted in a shortage of Chinese women.)

Refugees who wind up in South Korea face prejudice. Not used to making choices, they founder and are treated with contempt as slackers and losers.

The most tragic story in the book concerns the remaining South Korean POWs imprisoned by North Korea since the 1950s. They are elderly, too frail to endure an escape attempt. Many, Kirkpatrick surmises, probably don't even know the war has ended. "The United Nations, under whose flag they fought, has forgotten them.

"Somewhere in North Korea, five hundred South Korean prisoners of war have been held for nearly sixty years. They are unlikely ever to see their homeland again."

Although the United States welcomes North Koreans under the North Korean Human Rights Act of 2004, it hasn't done much to help them get out. The precarious underground railroad is still the would-be refugee's lifeline. Kirkpatrick, however, sounds a hopeful note. Since Lee Myun-bak became president of South Korea in 2008, he has pledged to do more to help fleeing North Koreans. South Korean consulates worldwide are under orders to give safe haven to North Koreans and help them find their way to a free country. In addition, information is starting to seep into North Korea, via Free North Korea Radio based in Seoul. Kirkpatrick thinks that a dissident grass-roots movement will eventually grow strong enough to topple the regime. But the key word is "eventually." We can't begin to say when Ground Hogs Day will end.

Brigitte Frase is a book critic in Minneapolis.