David Freed's first three Cordell Logan thrillers chronicled the former combat pilot and government assassin's struggle to adjust to civilian life. But in "The Three-Nine Line," Logan returns to his comfort zone when he's recruited for a top-secret overseas assignment.

The White House had hoped that a goodwill visit to Hanoi by several former American prisoners of war would help cement a critical trade deal with Vietnam, but when an aging prison guard who had once tortured the Americans is stabbed to death, the visitors are arrested for the murder.

Logan's task: find a way to spirit the heavily guarded Americans away to safety, discover who actually committed the murder and do it all without compromising the delicate trade negotiations.

Freed, an experienced pilot and a military affairs expert with an active security clearance, is also in his comfort zone, giving the novel an air of authenticity. The book's title refers to the combat pilot's need to keep enemy aircraft in front of him - in the "three-nine line" between the tips of the wings of his airplane.

The novel is a suspenseful, well-written thriller with enough plot twists to keep both Logan and readers wondering what will happen next. Along the way, the story explores raw feelings that still exist among veterans on both sides of the Vietnam War and touches on a host of contemporary issues from spy satellites to human trafficking.

But what makes each Cordell Logan novel especially enjoyable is spending time with the protagonist, whom Freed allows to narrate his own story. Logan is affable, funny and introspective. Through four books now, he's still trying, and often failing, to apply the principles of Buddhism to a life that's in constant conflict with them. And, unlike many of today's action heroes, he is uncomfortable with the violence he is so capable of and does his best to avoid it.