What I consider T.C. Boyle's greatest novels — "Drop City," "The Circle" and "The Women" and, indeed, much of his other fiction — revel mordantly in the characteristically American belief in the benevolence of nature, human and otherwise, and also in its corollary that justice and happiness flourish when freedom is absolute. "The Harder They Come" returns to the theme, again in a caustic way. The novel opens with a group of American retirees, cruise-ship passengers, setting out for a nice "nature walk" in the jungle in Costa Rica.

It is a nightmare, "with a surly thug for a driver and a shabby decommissioned school bus that had been painted over so many times it looked as if it had grown a hide." The outing ends in an armed heist during which one of the intended victims turns on the thieves, inadvertently killing one. It is a shocking business from start to finish and perfectly illustrative of how fragile is the membrane between order and havoc.

The reluctant hero of this episode is 70-year-old Sten Stenson, an ex-Marine and retired high school principal, who lives with his wife in a small California coastal town. Peaceful and affluent, the community is conscientious in its stewardship of the nearby state forest, a wilderness vulnerable to illegal large-scale marijuana growers, felling trees and poisoning animals.

The couple have one child, Adam, now in his 20s, mentally ill, living in the woods and answering only to the name Colter, an early 19th-century mountain man whose identity he has embraced. Life in the woods is scarcely the idyll he expected, and the young man becomes increasingly unstable, with lethal results. And Sten, first exasperated by his unwanted celebrity as a hero, finds himself in the ugly position of father to a killer.

Sten and Adam provide two of the three viewpoints out of which the story emerges. The third belongs to Sara Jennings, a radical libertarian in her late 30s, who is stopped by the police for not wearing a seat belt. ("Seatbelt laws were just another contrivance of the U.S. Illegitimate Government of America the Corporate.") That offense is compounded by her car being unregistered, and worsened again by her dog biting a policewoman. Circumstance, Sara's simplistic beliefs and Adam's survivalist paranoia bring the two together in an unwholesome alliance of mutual delusion.

The novel is a little loose in the seams: What went down in Costa Rica, though dramatic and illustrative of Sten's character, has only a rickety connection to subsequent events back in California. On the other hand, Boyle's tart and exuberant powers of description, of people and places, and his cheerful black humor are as exhilarating as ever.

Katherine A. Powers received the 2013 Nona Balakian citation for excellence in reviewing from the National Book Critics Circle and is the editor of "Suitable Accommodations: The Letters of J.F. Powers, 1942-1963."