Georgie has shingles so Lucia lets him stay at Grebe. After dabbling in the stock market Lucia's shares in the South African gold mine Siriami pay dividends and other Tilling residents join in. Everybody profits except Mapp and Major Benjy. Mapp and Lucia stand against each other for seats on the local council.

Neither Mapp nor Lucia win a seat at the local election. Mapp and Major Benjy are strapped for cash. Lucia proposes that they swap houses and is excited when she believes that she has discovered ancient artifacts buried at Mallards.

Lucia donates money to restore the Tilling church organ and to several local charities. She is also offered a seat on the town council. Mapp and Benjy, still living at Grebe, are flooded out and are forced to move in with Lucia. Lucia has stunning news.

Lucia marries Georgie and is made the mayor of Tilling. She selects Mapp as Lady Mayoress.

Lucia and Georgie travel to London and they meet Poppy who is interested in Georgie. Quaint Irene's portrait of Lucia as mayor is rejected while Irene's painting of Mapp has been declared the picture of the year. Lucia plots to regain her superiority as the social queen of Tilling.