Two astronauts, accompanied by their robot, set out to explore the surface of Venus. Things seem to be going well until violent changes begin to rework the surface. Will they be able to escape the planet with their lives? This film is also known as "Prehistoric Planet" and "Voyage to a Prehistoric Planet". This film began life as a Soviet-produced work. An American producer then added some new footage and changed the credits to hide the film's Soviet origin. The original film, "Planeta Bur", is also known as "Cosmonauts on Venus", "Planet of Storms", "Planet of Tempests", "Planeta Burg", and "Storm Planet".