The film is set in Africa roughly one million years ago, at a time when one species of "man-apes" (Australopithecus robustus) was being displaced by the ancestors of modern humans. These ancestors are possibly Homo erectus, but they are never named in the film. They are only addressed as "man" and from the few scenes where they show any visibility, they vaguely resemble modern humans.

The film follows the last of the man-apes (Peter Elliott) as he wanders through the wilderness after his tribe is slaughtered by the aggressive humans who have invented the ax and have learned to make use of fire. He journeys through a savanna, an oasis, a desert, and eventually the shores of a beach. Along the way, he avoids the humans that killed his family and witnesses many fantastic sights of wildlife. After experiencing a hallucination brought on by ingesting a hallucinogenic plant (possibly a reference to the stoned ape theory), he realizes the stone ax that he has been carrying after finding it at the site where his tribe was killed is a weapon. When he comes across a human footprint at the ocean shore, he sniffs it and then starts hitting it, wanting revenge against the humans. But he then relents and tosses the ax into the ocean. The closing scene has him sitting mournfully on the beach as the sun sets. The closing text states that the "man-apes" were likely the first species humanity pushed into extinction.

Missing Link is an unusual film in that it blends elements of drama, documentary, and avant-garde cinema. There is no dialogue, though there is narration (by Michael Gambon). There is also very little action. Instead, the film is filled with extended, picturesque sequences reminiscent of the style often used in nature documentaries. Perhaps due to its unconventionality, the film was not a commercial success.

• Missing Link at IMDb  
• Missing Link (1988) on Internet Archive