A thirty-four-year-old American woman—a secret agent—is sent to do dirty work in France. “Sadie Smith” is how the narrator introduces herself to her lover, to the rural commune of French subversives on whom she is keeping tabs, and to the reader. Sadie has met her love, Lucien, a young and well-born Parisian, by “cold bump”—making him believe the encounter was accidental. Like everyone Sadie targets, Lucien is useful to her and used by her. Sadie operates by strategy and dissimulation, based on what her “contacts”—shadowy figures in business and government—instruct.

The Overstory unfolds in concentric rings of interlocking fable that range from antebellum New York to the late 20th-century Timber Wars of the Pacific Northwest and beyond. An air force loadmaster in the Vietnam War is shot out of the sky, then saved by falling into a banyan. An artist inherits 100 years of photographic portraits, all of the same doomed American chestnut. A hard-partying undergraduate in the late 1980s electrocutes herself, dies, and is sent back into life by creatures of air and light.

In 1942, Lawrence Pritchard Waterhouse - mathematical genius and young Captain in the US Navy - is assigned to detachment 2702. It is an outfit so secret that only a handful of people know it exists, and some of those people have names like Churchill and Roosevelt. The mission of Watrehouse and Detachment 2702 - commanded by Marine Raider Bobby Shaftoe - is to keep the Nazis ignorant of the fact that Allied Intelligence has cracked the enemy's fabled Enigma code. In the present, Waterhouse's crypto-hacker grandson, Randy, is attempting to create a "data haven" in Southeast Asia....

Cyrus Shams is a young man grappling with an inheritance of violence and loss: his mother’s plane was shot down over the skies of the Persian Gulf in a senseless accident; and his father’s life in America was circumscribed by his work killing chickens at a factory farm in the Midwest.

When the enslaved Jim overhears that he is about to be sold to a man in New Orleans, separated from his wife and daughter forever, he decides to hide on nearby Jackson Island until he can formulate a plan. Meanwhile, Huck Finn has faked his own death to escape his violent father, recently returned to town. As all readers of American literature know, thus begins the dangerous and transcendent journey by raft down the Mississippi River toward the elusive and too-often-unreliable promise of the Free States and beyond.