The Overstory interweaves the stories of nine main characters whose lives become connected to trees and forests. The narrative spans multiple generations and locations across the United States. In the mid-1800s, Jørgen Hoel plants six
chestnuts on his Iowa farm. Only one survives a
blight, and subsequent generations of Hoels photograph this tree monthly. The tradition continues until Nicholas Hoel, an art student, finds his family dead from a gas leak. Olivia Vandergriff, a college student, experiences a near-death experience that leads her to join environmental activists in California. On her journey west, she meets Nicholas, and they join forces to protect
old-growth forests. Adam Appich, a psychology student, becomes involved with the activists while researching
group behavior. Mimi Ma, an engineer, and Douglas Pavlicek, a
Vietnam War veteran, also join the movement to save the
redwoods. Patricia Westerford, a
dendrologist, faces ridicule for her theories about tree communication but later gains recognition for her groundbreaking research. Neelay Mehta, a computer programmer, creates a virtual world inspired by the complexity of forest ecosystems. As the activists' efforts intensify, they resort to more extreme measures. Olivia, Nicholas, Adam, Mimi, and Douglas form a group that engages in
eco-terrorism, burning logging equipment. During their final mission, an explosion kills Olivia. The group disbands. Twenty years later, Douglas turns himself in to protect Mimi and identifies Adam as an accomplice. Adam, now a successful psychology professor, is arrested and sentenced to a lengthy prison term. Nicholas becomes a drifter, creating environmental art. Mimi changes her identity and becomes a
therapist. Neelay leaves his company and creates artificial intelligences to learn about Earth's biomes. Patricia continues her research and establishes a
seed bank to preserve plant species. She is invited to speak at a conference of influential people, where she delivers a powerful message about saving the world, before almost taking her own life onstage. Nick continues to make art, and the novel finishes with the completion of an enormous natural sculpture that spells out the word "STILL" big enough to be seen from space. ==Characters==