The incredible story of one man's obsession to find and protect the world's largest flowers As a child, Chris Thorogood dreamed of seeing Rafflesia - the plant with the world's largest flowers. He crafted life-size replicas in an abandoned cemetery, carefully bringing them to life with paper and paint. Today he is a botanist at the University of Oxford's Botanic Garden and has dedicated his life to studying the biology of such extraordinary plants, working alongside botanists and foresters in Southeast Asia to document these huge, mysterious blooms. Pathless Forest is the story of his journey to study and protect this remarkable plant - a biological enigma, still little understood, which invades vines as a leafless parasite and steals its food from them. We join him on a mind-bending adventure, as he faces a seemingly impenetrable barrier of weird, wonderful and sometimes fearsome flora; finds himself smacking off leeches, hanging off vines, wading through rivers; and following indigenous tribes into remote, untrodden rainforests in search of Rafflesia's ghostly, foul-smelling blooms, more than a metre across. We depend on plants for our very existence, but two in five of the world's species are threatened with extinction - nobody knows how many species of Rafflesia might already have disappeared through deforestation. Pathless Forest is part thrilling adventure story and part an inspirational call to action to safeguard a fast-disappearing wilderness. To view plants in a different way, as vital for our own future as for that of the planet we share.

And to see if Rafflesia itself can be saved.