John Wyndham was a British science fiction author in the 1950s. His most famous book is The Day of the Triffids, which I've written about before. Triffids was triffic fro 12 y.o. me: it fuelled a fantasy of making do with what was available in a survivalist self-sufficiency way. I was too insensitive to balk at the casual way in which the book disposes of so many people, and not just walk-on characters. Re-reading the book with adult eyes, it is driven by a messianic sub-text about who shall be saved. Not to mention a cliché sexism about the roles of men and women. I liked that book and read most of the rest of Wyndham's books including a Penguin volume of short stories.The Chrysalids [and his Midwich Cuckoos]. Eventually, resistance being useless, I caved and downloaded this other attempt at imagining a bleak post-apocalyptic future . . . where a small cohort of special folks are Saved. The conceit is that civilization has been burned to a frizzle and molten glass in The Tribulation a thermonuclear mutually assured destruction - a long long time ago. One of the fallouts of this nuclear war is a persisting drift of radioactive dust which mutates the inhabitants of Labrador; which escaped the immediate destruction. People are living in a post-industrial economy which looks like North America in, say, 1750.
A religious leader, also long gone, has set out definitions of what it is to be a) human b) suitable for humans to eat. Case b) are destroyed by fire, so that whole fields of corn which, on inspection, don't make the grade are conflagrated into the sky. Calves, chicks, foals, lambs are closely inspected for deformity and likewise summarily killed. Some backsliders, less able to take this loss, are liable to scarf down the offending animal to feed their families before they alert The Inspector. Some neighbours, in righteous indignation, will denounce this practice.
Case a) humans with the wrong toe count or too many freckles are treated differently. They are sterilized [Wyndham spares us the details of how this is achieved in a world without regular basic medicine, let alone state of the art surgical wards] and then exposed in The Fringes at the edge of their known world. Accordingly, Labrador is surrounded by Others, who have survived exposure and understandably bear a grudge against The Government which sent them forth into the wilderness.
The story centres on a small group of children who, although outwardly normal for fingers and freckles, are super different because they can communicate across distance by "thought shapes". They know that discovery will mean expulsion or worse. The narrator's sister is born and develops into a kind of super-telepath who among other things can message others a long long way away in Zealand.
In the climax of the story these latter-day Kiwi telepaths appear in a long-distance deus-ex-helicopter to air-lift our heroes to safety in a more tolerant civilisation on the far side of the World. As with a lot of Wyndham's bit-players, their attackers a casually choked to death by constricting filaments released by the rescue party; their bodies left to be eaten by the teratogenic monsters of the fringes.
Verdict: worth reading despite being the creation of a particular time when I was young and the existential threats were different. Probably not worth re-reading, though.