In 1851, private detective Laetitia Rodd is enjoying a well-earned holiday when she gets an urgent request for her services. Mrs. Rodd’s neighbor Jacob Welland is a reclusive rich gentleman dying of consumption, and he wants Mrs. Rodd to find his brother, who has been missing for 15 years.

Joshua Welland was a scholar at Oxford, brilliant, eccentric, and desperately poor when he disappeared from the university. Friends claim to have seen him since, in gypsy camps and wandering around the countryside. But the last sighting was 10 years before - when Joshua claimed to be learning great secrets from the gypsies that would one day astound the whole world.

Mrs. Rodd travels to Oxford and begins to search for the wandering scholar. But as she investigates, Mrs. Rodd discovers something dark - and extremely dangerous - lurking in the beautiful English countryside.