This unique made for TV movie has what most modern films do not have: a well constructed plot (or just a plot!), although simple, as the best often are. I don't think it has ever been shown on British TV since about 1980, though i know it has been shown at least twice altogether because i remember my dad telling me he had seen it (and giving away the ending!). The setting is an Antarctic research station staffed by 2 lone scientists throughout the winter, and otherwise occupied only by a collection of cute experimental chimpanzees. The bleak and menacing atmosphere given by the location is added to by the central mystery of the unexplained disappearance of the 2 researchers who staffed the building the previous year. Strange noises and unexplained little happenings occur throughout, and tension builds as it appears there is a someone or something prowling the premises. Now comes my spoiler: animal rights activists will LOVE the twist ending!