Beatrice follows the story of the Welsh title character Beatrice Granger, a teacher, and the affair that takes place with an unhappily married man in the form of barrister Geoffrey Bingham. Trouble awaits, in the form of Bingham's wife Honoria (who's only interested in money and social climbing), Owen Davies (one of the richest men in Wales, who is morbidly obsessed with marrying Beatrice), and Elizabeth (Beatrice's older sister, who will do just about anything to marry Davies herself).