One Dark Window by Rachel Gillig is the first book in The Shepherd King duology, a dark fantasy romance about Elspeth Spindle, a young woman in a mist-locked kingdom who must team up with a mysterious highwayman to find a cure for a magical plague, all while battling a powerful, ancient spirit called the Nightmare that lives in her head. The novel is known for its gothic atmosphere, lush prose, and slow-burn romance, blending familiar fantasy tropes with a unique magic system and a focus on Elspeth's internal struggle as the Nightmare's influence grows.
