The book details the everyday life of Mildred Lathbury, a spinster in her thirties in 1950s England. Perpetually self-deprecating, but with the sharpest wit, Mildred keeps busy with near-romances (her own and those of others), church jumble sales, and of course the ubiquitous cup of tea.
Mildred's life grows more exciting with the arrival of new neighbours, anthropologist Helena Napier and her handsome, dashing husband, Rocky - with whom Mildred fancies herself in love. Through the Napiers, she meets another anthropologist, Everard Bone, and it is with him that Mildred will eventually form a relationship.
A sub-plot revolves around the activities of the local vicar, Julian Malory, who becomes engaged to a glamorous widow, Allegra Gray. Allegra proceeds to ease out Julian's sister, Winifred, a close friend of Mildred's. Eventually matters come to a head and Allegra leaves the vicarage after a quarrel. In the meantime, Helena, who has been on the verge of leaving Rocky for Everard, accepts that Everard does not care for her and leaves the neighbourhood, along with Rocky.
As with most of Pym's books, the plot is less important than the precise drawing of the comic characters (such as Everard's elderly mother who is obsessed with the suppression of woodworm) and situations.