This short novel was written in 1988. In the realistic tradition, it is also a symbolic representation of the struggle between good and evil, an evil which takes the disquieting form of an alien creature introducing itself into the normality of everyday life.

Set in the Sixties, it deals with the story of a young couple, Harriet and David Lovatt. Conservative and old-fashioned, they feel strangers in the swinging atmosphere of their time. What they both want in life is a traditional family. Four children are born in their large country house where also relatives gather at intervals. A sense of achievement fills David and Harriet. But when a fifth child is announced Harriet feels from the start a hostile presence in her body. When the baby is born, "a muscular, yellowish, long creature", she "knows" that an alien being, a changeling, has arrived among them. Ben, this is the child's name, attacks his own brothers and sisters, kills the home pets, destroys the family. When the strain becomes unbearable, he is closed in an institution which, with "its rows of freaks nearly all asleep and all silent", recalls the scene of a horror film. Harriet decides lo bring him back home. He grows, goes to school where he is one of "the hopeless". Finally he joins a gang who start to drift into the house. Harriet understands that one day he will run away for ever with them, taking with him the mystery of his origin.

The message of this short, apparently subdued 'horror story' is conveyed in a neat, economic style, through a sequence of carefully detailed scenes. There is an impressive contrast between the warm family world described in the first part and the sullen atmosphere of the second. Here Lessing captures the shift in mood from the confident atmosphere of the Sixties to the grim world of juvenile gangs in the Seventies. The conclusion is deeply pessimistic: people refuse to see the child's real nature, as they refuse to see evil in general. Yet, there is an escape: in her growing maturity Harriet Lovatt understands she has to accept the existence of evil and survive through intellectual detachment.