In this film, the astronauts sent to explore a newly-discovered planet must deal with several dilemmas, and they do so intelligently. The film approaches it's main plot theme in a unique way, and unfolds it gradually, though it can be guessed beforehand.<br /><br />The acting is very good, though sometimes stiff, as some late-60s acting can be. It can also be somewhat wordy and even melodramatic, especially after the plot theme reveals itself. Visually, it has a scene that resembles one in the previous year's "2001: A Space Odyssey", and that tends to date the movie. Some of the actors went on to star in the 1970 TV show "UFO," which is delightfully campy and worth checking out on DVD.<br /><br />Despite these small points, the space flight itself is realistic, and considering this was 1969, the scenes inside the cockpit of the spacecraft also had a realistic look. (Look for some 1990s/2000s video technology in use, too!) One thing: I suspect a love scene has been cut, but I can't prove it! It would have been a distraction anyway.<br /><br />Unlike most Sci-Fi films, this film will make you think about the plot, and that's well worth a look. I'm pleased to have this film in my video library.