Space: 1999

Season 1, Episode 15

Episode Title: The Full Circle

Air Date: 1975-12-11

Overview:

When exploring a habitable planet, members of the Alphan survey party vanish without a trace. Are they the victims of an indigenous tribe of Stone Age humanoids? The mystery deepens when a dead caveman is found to have capped teeth. Others soon notice the primitive cave chief and his mate bear an uncanny resemblance to the missing John Koenig and Helena Russell.