The Tebricks, a charming, young, upstanding couple, remove to Oxfordshire to begin their married life, happily unaware of the future awaiting them. When Sylvia turns suddenly into a fox, their fortunes are changed forever, for all her strenuous attempts to adhere to the proprieties of her upbringing, and resist the feral instincts of her current form. Increasingly cut off from the world, Richard does all he can to protect his wife from the dangers inherent in the world outside their grounds, dangers which are impossible to fight, and which inevitably break down the boundaries between them and the world beyond the garden walls.