Barbara goes for an interview in a house where it appears there are no children. The mystery is explained when she learns that her prospective employers have decided to adopt two slum children as ' an experiment ', Deeply suspicious, Barbara nevertheless feels this is a challenge she cannot let pass.

Barbara has gone to work for a highly-successful self-educated inventor and his family of hangers-on in a remote part of Suffolk. Fond as she is of them, she is driven to the point of exhaustion by the helplessness of the household. Then, on her day off in Ipswich, she meets someone...