Fern has spent her whole life in the rainforest with her botanist parents, and loves nothing more than climbing, exploring and talking to the trees. But when she suddenly has to leave all that behind and move to London, finding only an eccentric uncle for company, Fern feels entirely uprooted. That is until she finds a little plant, one that can move and dance and seems to understand her every word. Can a plant really be this special – and be her new best friend? But when the secret plant starts to wilt, Fern finds that she needs her new London family to solve the mystery of where her magical friend came from – and how to save its life.