Alfred Dorset and his sister Louisa are old, unmarried, and living together in the shabbiest house in the lane, selling figs and paper flowers for money. They often talk about how much they dislike their family; their parents were distant cousins, but the Dorsets refuse to get married and instead claim to have "given up everything" for each other. Their neighbors dislike the way they dress and behave, but they send their children to the yearly party held by the Dorsets anyway. This party is exclusively for "the young," and over the years it has become a rite of passage.

Alfred drives around picking up children and driving them to his house, where they are welcomed by Louisa. The Dorsets dress up elaborately, provide food, lead the children on a tour of their house, and end the evening with dances-—just the two of them, dancing to music records.

One year, Ned Meriwether and his sister Emily decide to do what no child has ever done before: sneak in an uninvited guest to the party. This intruder is Tom Bascomb, the newspaper boy in Mero. Ned exchanges clothes with Tom, and Emily then introduces him as her brother to Alfred. The Dorsets don't take close interest in the children they invite, since they are more interested in youth than anything else, so Ned is able to join the party just before Louisa opens the door.

For comedic potential, the children had planned that Tom and Emily should kiss. The Dorsets see nothing wrong with this, exchanging indulgent glances. The other guests giggle, but Ned feels strangely uncomfortable. This charade carries on until the dance, after which Ned shouts that Tom and Emily are siblings. The party treats this as a joke, and the Dorsets turn on Ned, deciding that he is the intruder and not Tom. Alfred chases Ned into an upstairs bathroom and locks him in, while Tom telephones the Meriwethers and leaves hastily. The worried parents come quickly, and Louisa pathetically claims that the children are all playing a prank on her. Alfred storms away into his room, and the Meriwethers take Emily and Ned home.

After this incident, the Meriwether children are sent off to boarding school and the Dorsets never have another party again. They stop selling figs and flowers and do not make public appearances. The children grow up; Ned and Tom leave to fight in the Second World War. Ned marries a woman he met in the Navy and they move back to live in Mero. Whenever the woman is drunk, she is fond of bringing up the story of Tom Bascomb and the Meriwether siblings, who have been distant from each other ever since the Dorset party.