Once-in-a-Millennium Genius Finn Chandler leaves Tiger Village after completing his training, returns to Harbor City to fulfill his marriage contract with CEO Zara Hale, and takes a job as a security guard at Ascend Group. Facing corporate crises and family conflicts, he uses his skills to work through difficulties alongside Zara and their partners, as the two gradually resolve their differences and build trust. At the same time, Finn investigates his family's past and searches for his long-lost younger sister. With the help of everyone, he helps the company pull through its hardships, rescues his sister, and follows new clues to continue uncovering the truth, protecting his family bonds and promises.