An unsettling — and sadly familiar — image casts a long shadow over Matthew Quirk’s new novel: “a pile of bodies, many dozens, heaped like trash in a landfill — men, women, children, some 2 or 3 years old, all of them torn apart by gunfire.” A mass execution at a U.S. military base overseas has left hundreds dead, but the worst atrocity is that the attack seems to have come from a Special Operations group using the base for clandestine maneuvers.

Cold Barrel Zero,” Quirk’s third novel following “The Directive” (2014) and “The 500” (2012), is a relentlessly paced military thriller that begins in Los Angeles with the high-speed ambush of an armored truck, which may be carrying a weapon of mass destruction, and ends with a suicide bomber outside a private school in Washington (Sidwell Friends). In between, there’s a flurry of gunfights, a car chase, a boat attack and torture scenes vivid enough to make your skin curl.

Col. Riggs, who headed the ill-fated base and was wounded in the initial attack, is pushing the government for unprecedented leeway to “fight the enemy as they fight us.” Meanwhile, Special Operations soldier John Hayes and his team, branded war criminals in the massacre’s aftermath, have stopped hiding and begun running toward their accusers. Their motives are as uncertain as the ones surrounding the attack itself.

Caught in the crossfire between these two groups is doctor Tom Byrne, who once served under Hayes as a combat medic and who remains haunted by all of the deaths for which he feels responsible, “these shades that followed me around.” Pulled reluctantly into a fresh kind of combat zone between former loyalties and damning accusations, Byrne also finds himself drawn back into his past. There are layers of moral ambiguity and questions at every turn. What should he do? Whom can he trust? Byrne tells his story in the first person, while the book’s other sections jump through other narrative perspectives. Perceptions and alliances shift just as quickly.

The author Matthew Quirk (Mark Finkenstaedt)

Despite sophisticated storytelling, “Cold Barrel Zero” indulges in formulaic elements. Too often, chapters end on a cliffhanger — frequently sleight-of-hand tricks rather than solid suspense. Action scenes stumble through definitions of weaponry and hardware, their purposes, their implementation — shoehorning in the kind of expertise Quirk probably earned as a reporter for the Atlantic covering military contractors and terrorism. Elsewhere, during various race-the-clock moments come wooden emotional revelations (“I haven’t felt this way about anyone in a long time. I didn’t think I could. Until you”). Inevitably, other loved ones near and far are drawn into danger, but the good soldier always puts country and duty first, right? (“God forgive me. . . . This is where I need to be.”)

But probably none of that matters amid the novel’s whiplash pacing. “Cold Barrel Zero” delivers clever twists and startling surprises, the full story coming into focus only when all of the parts are assembled.

Art Taylor is a professor of English at George Mason University and the author of “On the Road With Del & Louise: A Novel in Stories.”

cold barrel zero

By Matthew Quirk

Mulholland. 373 pp. $26