Rachel goes to Spain, a country she's always admired, after having a fight with her father. She has two goals: to find her mother, who she was told had died, and to get out of her marriage of convenience. Needing money for her trip, she decides to work as a secretary for Luis, who owns a gray castle on a hill. He has black hair and smoky, quartz-colored eyes that hint at danger, but she can't keep her eyes off him. Secretary and boss—both have their own untold secrets, but will they stay secret when a passionate love flares up between them?