Five more episodes from the classic animated puppet sci-fi series, created by Roberta Leigh. In 'The Miracle Tree of Saturn', Dart is sent to get some more supplies from Saturn's sacred tree in order to save the crops from a poisonous fungus. In 'The Cloud of Death', Tyro, the Neptunian leader, threatens to freeze Earth unless Raeburn sends human slaves to work for him. In 'The Planet of Thought', Tyro uses his hypnotic powers to lure Maria back to Neptune, where he plans to make her his princess. In 'Explosion on the Sun', Dr Duncan causes the temperature to rise on Earth and Venus by firing beryllium into the sun. He then threatens to do so again unless weapons are sent to Ganymede. Whilst in 'Volcanoes of Venus', Venus is being paralysed by a virus, caused by a powder released by Gallia, to help him seize power.