Tessa Shea, a modern military doctor, travels through time and becomes a notorious daughter of a marquis. On her wedding night, she is caught in an adulterous act by Prince Liam Tate. The Third Prince Neil Tate forced the original self to marry Prince Liam to spy on him. To save her own life, Tessa uses her medical skills to sign a contract with him. She will cure his illness, and after that, she will leave. However, as they face crises together, trust gradually builds between them. Later, Tessa finds herself pregnant. Fearing that Prince Liam will kill her, she escaped. What neither of them knows is that the person they spent that night with was none other than each other...