Set in the 19th century in Scotland, Lydia Carlton earns her livelihood as a fairy doctor, gifted with the ability to perceive and interact with fairies, a talent doubted by many. When Edgar, seeking her expertise in fairy lore, saves her from a predicament, he hires her. Yet, mysteries and sentiments enshroud Edgar, who identifies himself as the Earl of the Blue Knight, weaving a tale of intrigue and enchantment.