Horizon investigates a strange skull that was discovered in 1848 on the military outpost of Gibraltar. It was undoubtedly human, but also had some of the heavy features of an ape... distinct brow ridges, and a forward projecting face. Just what was this ancient creature? And when had it lived? As more remains were discovered one thing became clear, this creature had once lived right across Europe. The remains were named Homo neanderthalensis (Neanderthal man) an ancient and primitive form of human.