In an extraordinary era, the special story of ordinary people who wanted to live an ordinary life begins! Detective kang, who works diligently to catch criminals and is loyal to the country, with his loving wife (la mi-ran), and jin, a father who aspires to live a comfor life in a two-story traditional korean house with his son. On a day like any other, while tirelessly working on apprehending criminals, jin coincidentally apprehends a suspicious suspect, tae-sung (jo dal-hwan), and discovers evidence that tae-sung might be the first serial killer in south korea. As a result, he unwittingly becomes deeply involved in a secret operation led by director gyu-nam (jang hyeok). On the other hand, ja-jin (kim sang-ho), a journalist from the freedom daily who is like family to jin, notices something suspicious during his coverage of the case and advises jin to step back at this point. However, jin has made a promise to his son, who is disabled, to undergo surgery and reluctantly accepts gyu-nam's uncomfor proposal. This choice, made out of his role as a father, ironically puts jin and his family in even greater danger and starts to shake his life to its core...