Both Clent and Garrett are part of a team operating this ionizer in order to melt away the glaciers that threaten the UK which they are apparently in and the rest of the world. This is the result of a second ice age humanity created in error when they invented a synthetic food and destroyed all the plant life to house the growing population. Without carbon monoxide,the Earth became devoid of life and entered into a second ice age. Meanwhile Arden,a scientist working with Clent discovered what he believed to be some sort of cave man under such a glacier and enthusiastically returned it to the dome for investigation.
After observing the creature,the doctor realizes that this is actually an ancient astronaut with no terrestrial origins and that what they believed to be head armor was actually a sophisticated space helmet. Meanwhile in the dome's lab,Victoria is being menaced by this Ice Warrior who identifies his origin point as being Mars,and wants to know what Victoria knows of his crashed spaceship and crew. He takes her hostage and,when the doctor discovers this he sends Arden and Jamie out to rescue her from the talons of the Ice Warriors who abducted her.
While Arden and Jamie find the Ice Warrior's ship frozen in the ice,they are shot by one of them-leaving Arden dead and Jamie severely injured. Having failed already in numerous attempts to escape the Ice Warriors,Victoria pretends to agree to help them by contact Clent in order to reveal the location of the ionizer,which they believe is going to be used to destroy them and whose fusion fuel they intend to use to refuel their spaceship. In the meantime Jamie is dragged away by Penley,a scientist who left Clent behind on a matter of difference and the scavenger Storr-who distrusts science altogether.
During an attempt to return Jamie to the base,Penley escapes an attempt from Miss Garrett to sway him into helping the mechanized mind Clent into stabilizing the ionizer permanently. Meanwhile Storr journey's to the Ice Warrior's spaceship in an attempt to convince them that he is allied with them against Clent and his fellow scientists. He too is killed the the Ice Warriors. Having heard Victoria's plea,the doctor has now joined her and attempts to use a "stink bomb" toxic to the Ice Warriors to fascinate an escape attempt. Narrowly making it out, the doctor realizes the Ice Warrior's highly liquefied body makeup and devises a possible new defense for Clent and his base.
Returning to the base where Clent is futally trying to reason with Ice Warrior Varga,the doctor manages to alter the oxygen and gravity level in the computer area in such a way that Ice Warriors,
including the callous and threatening Varga, are all destroyed with minimal physical damage to Clent and his team. With the recovered Penley's knowledge of the "Omega Factor" at hand,he is able to cooperate with Clent and the doctor enough to save the faltering fusion ionizer and their mission. While Clent and Penley finally come to an agreement,they find the doctor and his companions have disappeared (back to the TARDIS) before they have a chance to thank him.
There are many layers to this densely written (some more cynical critics might say convoluted) 1967 story. The Ice Warriors place absolutely no value on human life and morals-only seeing what they need and what threatens them. They are even impassive to the constantly crying,screaming and understandably frightened Victoria's pleas to return to the doctor and Jamie. There is also Leader Clent-with almost an addiction (along with his employee Miss Garrett) to the need of their computer that has made all of their decisions for them,yet is faltering fast at the abundance of inconsistencies clouding its logic.
The basic plot of the story actually addresses the early stirrings of the global warming concept effected humanity today in real life. And again,with the more well rounded approach of the scientist Penley,the enthusiasts approach of Arden and the agrarian Storr are also ahead of their time as they showcase possible alternate sides on the fictional climate change and mind-over-machine dilemma faced in this story. Miss Garrett tries to be the calm middle ground. But in the end remains loyal to Clent and his computer. So it is the doctor and Penley who end up representing balanced scientific rationalism in dealing with both Clent's ionizer dilemma and the Ice Warrior's intrusion in this compelling and futuristically topical story.
