"SOMEWHERE INSIDE: One Sister's Captivity in North Korea and the Other's Fight to Bring Her Home," by Laura Ling and Lisa Ling, William Morrow, 317 pages, $26.99.

In March 2009, broadcast journalist Laura Ling and her team enter China for another routine assignment.

Ling, a reporter for former Vice President Al Gore's news outlet, Current TV, was filming a report on North Korean defectors. Attempting to escape North Korea's crushing poverty, defectors cross the border into China. Because China views the defectors as illegal immigrants, the defectors hide, living in fear of capture by Chinese authorities. Most of the defectors are women. What awaits them across the border is not a safe haven but traffickers who sell them as wives or prostitutes.

The place where many North Korean defectors cross into China is a span of the Tumen River. With the aid of a local guide, Ling and her team go to the frozen river to film the well-used crossing. Lured by her guide, Ling walks across the river — and very briefly steps into North Korean territory. North Korean guards emerge and chase the trespassers across the ice to the Chinese side of the river. Ling's producer/cameraman escapes, but Ling and her co-producer/translator, Euna Lee, are captured and beaten by the North Korean soldiers.

Ling and Lee are detained and questioned about their reasons for being on the river. Fearful of the North Korean soldiers finding out they are journalists, they pretend to be students. But as their time in captivity lengthens, Ling, separated from Lee, begins to parcel out more of the truth to her interrogators, walking a fine line of what to reveal and what to conceal, not knowing what information will help her and what will hurt her. "I began to look at each day as a strategic puzzle," Ling writes, "one I had to solve in order to win back my freedom."

Most of all, Ling wants to keep secret the fact that she is the sister of broadcast journalist Lisa Ling, who, several years earlier, had entered North Korea under the guise of being part of a medical team and filmed a documentary critical of the communist nation.

Months after their capture, Laura Ling and Lee are tried for "hostile acts" against North Korea and sentenced to 12 years in a labor camp.

At home, Lisa Ling is hit hard by her beloved sister's capture and begins mobilizing a rescue effort. The well-connected journalist calls on a list of Washington luminaries, including Gore, New Mexico Gov. Bill Richardson, Sen. John Kerry, Secretary of State Hillary Clinton and former President Bill Clinton.

"Somewhere Inside" is written in alternating chapters by Laura and Lisa Ling.

Laura Ling's story, obviously, is the more compelling. Hers is a sometimes harrowing, sometimes surreal, sometimes mundane account of her nearly five months in prison.

The written word is not these broadcast journalists' forte, and passages of "Somewhere Inside" that should pull at the heartstrings are dry and flat. Yet the bond between the two sisters and the account of their ordeal is compelling enough to keep readers turning the pages.

e-mail: jwilliamson@desnews.com