The breathtaking story of a lost 19th century Geographical Society expedition into darkest Africa. George and Alexandria Lipton must leave their young son behind in England when they depart for the jungles of Gabon. The couple lead a disparate group of academics and mercenaries on an expedition to find the legendary pygmy tribe, the Batwa. They tell their young son that they will be back by the time that there is snow on the Downs, but that is before they actually find the lost tribe and discover the terrible secret of the Monkey Nuts.