"The Midnight House" by Alex Berenson

John Wells is back, lean and just mean enough. Alex Berenson has published three previous thrillers about Wells, legendary for being the only CIA agent to penetrate al-Qaida and for narrowly averting a terrorist attack on Times Square.

In Berenson's fourth novel, "The Midnight House," Wells is living in seclusion in New Hampshire, hiking with his dog and not much interested in adding to his legend.

Then his old boss calls. It seems someone is murdering former CIA agents, all of whom were part of a unit called Task Force 673. Its 10 members did their work in a secret Polish prison in 2007, interrogating high-value detainees between their capture in Afghanistan, Pakistan or Iraq and their official imprisonment at Guantanamo.

That in-between otherwise known as rendition isn't supposed to exist, and neither is TF 673. But its members are being hunted down and killed, beginning with the unit's psychiatrist, Dr. Rachel Callar. Her death was made to look like a suicide, but the others are clearly murders. Wells' bosses the ones at the very top of the food chain want it stopped, but the investigation, of course, can't exist either.

Berenson, who has covered the Iraq war for The New York Times, does a fine job with the book's globe-trotting settings and satisfyingly twisted plot.

Wells is a refreshing thriller hero, sort of the anti-Jack Bauer. Although "The Midnight House" has its share of cinematic firefights and fisticuffs, we more often see Wells pursuing the real work of spycraft: learning a culture well enough to blend in (whether in Pakistan or Langley), listening to people closely enough to see what's going on behind their words, practicing patience.