The movie starts with Professor John Oldman packing his things to leave and start a new life. He invites his friends to say goodbye and decides to reveal the reason for his departure. The starting point of the narration is a simple question asked by Oldman to his friends: what would a man from the upper paleolithic look like if he had survived until the present day? As scientists, the protagonists play his game and investigate the question, not knowing whether the story is a bad joke or a genuine narration. One of the best movies I've watched and definitely one of the most under-rated.