They make themselves comfortable in an old barn and light a fire to keep warm. They are disturbed by a noise outside and prepare to defend themselves.
Their visitors are some dishevelled young travellers, a man called Kim and a mute girl called Susan. Pet and Charles invite to share their fire and shelter. The couple tell them they were forced to leave a nearby settlement. During the night, Charles and Pet are kept awake by the couple have become violently ill.
Charles and Pet take them back to the settlement they talked about to obtain help. A sentry refuses them entrance when he recognises the young couple. However they are granted access when they tell him they have salt which they will trade for assistance.
The four are put into a quarantine hut in the settlement, which is actually an old army camp. Charles and Pet try to make Kim and Susan comfortable, but it is clear that they are both very unwell.
The sentry who is called Lenny goes to tell the settlement leader, Max Kershaw, and his deputy, Joy Dunn, about the new arrivals. Charles and Pet explain the situation to them, but they seem to have little compassion for the couple.
The leaders go to talk to a man called Sammy, who discovers that the couple are ill because they stole and ate some seed wheat which had been coated with a fungicide containing mercury. The girl is now dead. Joy tells Pet and Charles what has happened and explains that the man will die soon as well.
Charles is treated to a meal by Joy and she explains a little about the social system at the settlement. She explains that they believe in selective procreation, no individual marriages and physical development. Charles likens it to the kibbutz system and asks to speak to Kershaw so he can discuss the possibility of links between the community and Whitecross.
Charles is angry to learn that Kim has been disposed of by Lenny. Pet shares her concerns about the settlement with Charles. Whilst he was talking to Joy she has seen fieldworkers marching to work and back, which she thinks is unnatural. Charles thinks she is overreacting and is still optimistic about future links with the community.
Meanwhile the settlement's committee is meeting to discuss Charles and Pet and what they see as their Marxist style settlement. Despite reservations about the new arrivals degenerate philosophy they are all agreed that they need to know their source for the salt. Joy tells Charles and Pet that the committee will see Charles that evening. Pet is concerned about her boots, without which they can't really leave. Joy tells her they will be ready for the morning.
Pet is still concerned about their safety there and after Charles goes to the meeting she bolts the door to their quarters and stands by with a gun. Charles discovers early in the meeting that the committee are diametrically opposed to his ideas, believing as they do in controlled breeding. They actually see random mating as criminal folly.
More alarmingly, they also believe that the death was inevitable due to mankind's genetic decline. They see the plague as an act of God and themselves as 'the chosen', and are determined not to be polluted with 'old world ideas'.
They also criticise Charles collaboration with the young couple, who they call 'termies' (terminal cases) seeing this sort of assistance as ultimately leading to degeneration. Charles tells them he can see no mutual interests for his community and theirs and refuses to tell them where they go for their salt supply. He does suggest however that he be allowed to address the rest of their community to see how they would react to what he has to say. They agree to this request.
Later that night Joy persuades Max that Charles and Pet should go as they will cause dissention amongst the community if they are allowed to speak the next day. Max tells Charles and Pet to leave, bringing the latter's boots with him, claiming that he thinks it would be dangerous for Charles to speak as the community may turn on him.
Joy visits Charles and Pet a little later, advising them not to leave, claiming that Max will have them shot them on sight. They follow her advice and stay the night.
At the meeting the next day Charles is not given a chance to speak as instead Joy turns on him accusing him of endangering the community by bringing the termies in to the settlement.
She then turns her attention on Max, claiming that he has become corrupted by power and has been deceiving the community. Max denies this but she argues that he had planned to kill Charles and Pet and that he had set up a plan to have members leave the community only to return later begging to be let back in. The community are clearly behind Joy as she finishes her tirade against Max.
Max is deposed as leader and Joy takes his place. Charles and Pet are free to go. Joy tells Pet that Max will be pardoned. She sees them off the camp with Lenny.
Pet and Charles discuss how Joy used them to seize power and tone down Max's regime which had become to extreme. Pet suggests that she may have been nervous about her position there due to their euthanasia policy and the fact that she was too old to bear children. Pet jokes that she would be an ideal candidate for the first prime minister of the new world and adds that politicians are always the survivors.
The Chosen is a welcome break from the norm that has become the Whitecross soap opera. Here we have a refreshing episode which more than nods to the format of the third series, during which we witness the exploits of two of the regulars as they experience the world beyond their cosy community.
Thankfully it is the likeable couple of Charles and Pet who are the regulars in question. That Pet is finally out of that kitchen is a reason for cheer, her character having been criminally underused...