Director "Derek Thomas" is actually Peter Bogdanovich.
The "Prehistoric Women" do not appear in the original Russian film from which this was made.
The footage of the astronauts is actually from a Russian sci-fi film, Planeta Bur.
This is actually a re-edited version of a film previously released in the U.S. as Voyage to the Prehistoric Planet, which itself was an edited and dubbed version of the Soviet film Planeta Bur. For this version the already dubbed Russian footage was re-used but the American insert shots of Basil Rathbone and Faith Domergue were removed and new insert shots featuring Mamie Van Doren and other actresses (as inhabitants of Venus) were inserted. Director Peter Bogdanovich did the narration as if he were one of the cosmonauts telling the story in flashback. Some additional special effects shots from another Soviet production, Battle Beyond the Sun, were also added. For this version, the famous shot of the Venusian reflected in the pool of water was removed.