The Chrysalids is a science fiction novel by John Wyndham, first published in 1955 by Michael Joseph. It is the least typical of Wyndham's major novels, but regarded by some as his best. An early manuscript was entitled Time for a Change.The novel was adapted for BBC radio by Barbara Clegg in 1982, with a further adaptation by Jane Rogers in 2012. It was also adapted for the theatre by playwright David Harrower in 1999.Plot summaryA few thousand years in the future, post-apocalypse rural Labrador has become a warmer and more hospitable place than it is at present. The inhabitants of Labrador have vague historical recollections of the "Old People", a technologically advanced civilization which existed long ago and which they believe was destroyed when God sent "Tribulation" to the world to punish their forebears' sins. The society that has survived in Labrador is loosely reminiscent of the American frontier during the 18th century.The inhabitants practise a form of fundamentalist Christianity with post-apocalyptic prohibitions. They believe that in order to follow God's word and prevent another Tribulation, they need to preserve absolute normality among the surviving humans, plants and animals. Genetic invariance has been elevated to the highest religious principle, and humans with even minor mutations are considered "Blasphemies" and the handiwork of the Devil.