A complete introduction to the hidden world of fungi. The kingdom of fungi has survived all five major extinction events. They are the architects of the natural world, integral to all life. They sustain critical ecosystems, recycling nutrients and connecting plants across vast areas, and help to produce many staples of modern life, such as wine, chocolate, bread, detergent and penicillin. Today, in the face of urgent ecological, societal and spiritual crises, fungi are being engineered to grow meat alternatives, create new sources of medicine, produce sustainable biomaterials, remediate the environment and even expand our collective consciousness.