It is a sultry August in the last decade of the 19th century, and the Davies household has visitors--the querulous old tyrant Professor Alexander Blathwaite, absentee owner of the estate and his second wife, the much younger, American-born Helen. They impose their London ways and thoughts on the more rurally-based family, which consists of Ieuan, the middle-aged brother of Blathwaite's first wife, the professor's plain daughter Sian and her grandmother, Ieuan's mother, Mair Davies. Ieuan, who has managed the estate for many years for little reward, has fallen passionately in love with Helen, but his passion is, as yet, unrequited. Sian, his niece, is also secretly in love, with Dr. Michael Lloyd, an idealistic conservationist who is growing increasingly disillusioned with country life. In a series of tragi-comic episodes, the ordered Victorian calm of the Blathwaite household begins to disintegrate over one pivotal weekend.