When civil engineer Cael Ward dies in a construction accident at age 30, the last thing he expects is to wake up in the body of Sarek Ashford—the useless, debt-ridden third son of a minor noble family in the Kingdom of Morcelon. According to the novel he had been reading, Sarek is destined to bankrupt his family within two years, leading to their execution when they fail to pay taxes to the tyrannical Duke Alde.

Armed with modern engineering knowledge and a desperate need to survive, Cael begins implementing infrastructure projects to save the failing Ashford estate: aqueducts to bring fresh water, proper sewage systems, crop rotation to improve harvests, and revolutionary construction techniques. What should be impossible for a medieval world gradually becomes reality under his guidance, transforming the estate and surprising the local nobility.

Enter Lord Ryn Alde. The Duke's younger brother and Commander of the Knights, Ryn is everything Cael expects from the novel: devastatingly handsome, politically brilliant, a master swordsman, and tasked with inspecting the Ashford estate. In the original story, Ryn was a minor character—the cold, duty-bound knight who eventually signed Sarek’s family’s execution warrant. But Cael’s presence changes everything. The icy knight, unshaken by treacherous politics and ruthless nobles, starts visiting weekly to “supervise construction projects” and finds himself puzzled by the strange lord who talks of mathematics, physics, and impossible ideas.