In the vein of Susan Orlean’s The Orchid Thief, journalist Emily Brady journeys into a secretive subculture — built on marijuana.

Outside the United States, the words ‘Humboldt County’ mean little. Inside the United States — the home of the war on drugs — those words can prompt a knowing grin.

Humboldt is a narrative exploration of this insular community in northern California, which for nearly 40 years has existed primarily on the cultivation and sale of marijuana. Emily Brady spent a year living with the highly secretive residents of Humboldt County, and her cast of eccentric, intimately drawn characters take us into a fascinating alternate universe — a place where business is done with thick wads of cash, and savings are buried in the backyard.

But as legalisation looms, the community stands at a crossroads, and its inhabitants are deeply divided. Humboldt tells the story of a small town that has become dependent on a forbidden plant, and of how everything is changing as marijuana goes mainstream.