The Wild Trees by Richard Preston is a fascinating and compelling work of narrative nonfiction. It might read like a thriller, but it tells the true story of a quirky bunch of botanists and amateur naturalists who share an almost obsessive passion for the titans of the tree world: the West Coast redwoods.

Richard Preston, who is also a tree climber, traces the lives of Steve Sillett, Marie Antoine, Michael Taylor, and others from their early fascination with trees and botany to their single-minded devotion to researching what remains of the American rainforest.

That quest led them to each other and into the unexplored world of the redwood canopy. Steve and Marie came to their discoveries through academia; Michael worked in a supermarket but spent every weekend hiking through impenetrable undergrowth to find his holy grail—the tallest tree.

They risked their lives to identify and explore those trees; they named them and connected with them on an almost spiritual level. Michael, who is terrified of heights, stayed mostly on the ground, but the others camped up in the canopy in hammocks called treeboats. They looked down on the forest at night, made love up there, and weathered dangerous storms that threatened to plunge them to certain death. They swung from tree to tree as they mapped crowns and recorded the intricacies of one-thousand-year-old organisms.

We follow them through the dangers of their early attempts to measure and scale these living giants. We see them invent the techniques now used for climbing massive trunks that can reach up to thirty feet wide and sore thirty-five stories into the sky. And we’re along for the ride when they enter a hidden world three hundred feet above the ground. They explore caves, majestic wooden bridges and towers, and discover hanging fern gardens, shrubs covered in berries, and other trees growing in soil that has traveled up into the canopy to create a secret biosphere. How magical is that?

If you love exhilarating stories of exploration, this is the book for you.