When I saw that this film was being aired on late night TV I initially decided to give it a miss. I am glad that I then started watching. Yes the special effects are the same as Gerry Andersen's puppet shows. Some of the actors/actresses are from his other productions, he obviously used the same composer later on, as the cheesy soundtrack could only have come from one of his productions, and the plot is as slow as a wet weekend. Get by all that and you have a film that shows up intriguing possibilities. Is there a planet on the far side of the sun? Is it a duplicate earth? Is everything about it reversed and if so do they speak English in reverse? I love this dated SF if only for Gerry's wonderful model cars, planes, buildings and spaceships. Some of them are not so far fetched as they seemed back then. And did you see the European Space Centre logo? Very reminiscent of the Euro logo of today. Suspend belief and spend a couple of hours watching this, you will be glad you did.