A Welsh village and its people are used to dramatise the lives of the people of Lidice, showing their way of life before, and their fate after, the Nazi invasion of Czechoslovakia.

Cwmgiedd is a peaceful, harmonious village where the men work down the mine and relax in the pub and the women make the tea and enjoy a night out at the cinema with their children. With the arrival of the Nazis, however, it becomes a place where there is no escape from the insidious presence of the invader. This presence is characterised by a voice, which first of all enters their streets - through a megaphone attached to the roof of a silently gliding car - and then their homes, via the radio. The people resist oppression and thereby incur the wrath of the Nazis: the men of the village are shot, the women are sent to concentration camps, the children appropriated by the authorities and the village physically destroyed. But the Nazis have reckoned without the spirit which prompts such heroic stands for justice - a spirit shared by miners throughout the world, and which ensures that Lidice and its people will always be remembered.