The forest floor is perhaps the worst and most inhospitable place of all - dark, damp and full of potentially dangerous wildlife. Nowhere is more forbidding than the original heart of darkness: the Congo. To survive here, almost everything has to struggle for light. Charlotte is confronted with walls of impenetrable poisonous plants, toxic snakes and spiders, killer ants, diseases and large predatory cats. She can't sit down without being bitten. And at night, it's even more frightening, full of strange sounds and even stranger creatures. It takes considerable dedication to overcome the hazards but Charlotte uses field craft and state of the art technology to reveal the hidden world of the forest floor. This is a world of the smallest and the largest. The termites and microscopic fungi are the great recyclers of forest waste, and cause of foot rot! It is a world of chemical warfare between plants and animals, with plants producing poisons that are harmful to touch, and trees hosting armies of ants to defend them against would-be animal attackers. This is an undercover world of subterfuge, secrecy and camouflage. Nothing is as it appears - venomous snakes look like leaf litter and invisible flies carry fatal diseases.