Jack Boult, a former rally driver, and his second wife Harriet, who used to be a nurse, move from the bustle of London to start a new life in a cottage in the Somerset countryside, together with Jack's children Freddy and Tom. With the help of Lady Patricia Broughall, a local landowner, and Hilly, a girl who lives in a railway carriage in the woods, they become involved in tackling various environmental issues such as badger-baiting and horse-stealing.