The Northern Realm is ruled by magic and ancient pacts. Eileen, a young female pharmacist, sees her father executed for treason and her family exiled. To save her younger brother, she is forced to marry Kane, the lord of Blackstone Castle who is rumored to control shadows, as a "war trophy bride" from a rival family. What seems like a humiliating political marriage is actually Eileen’s plan: she wants to sneak into the castle to find the truth about her father’s frame-up and steal the contract scroll that can clear her family’s name. Kane sees through Eileen’s hidden agenda, and the two confront each other and test one another at every turn. As they get along, Eileen discovers Kane is not as cruel as rumored—he silently bears infamy for the royal family; Kane is also moved by Eileen’s stubbornness and kindness, and desires to protect her. But when Eileen finds the scroll, she is shocked to learn that Kane signed the order to execute her father. In the end, they put aside their grievances, join hands to expose the royal scandal of refining magical energy with living people, clear her family’s name, and Kane gives up his military power. This forbidden marriage blooms into a symbol of freedom and true love atop the ruins.
