Shin Cha-il joins JU Construction's Audit Team as the new head. After meeting the team, he has nothing more to say than to ridicule their incompetence and laziness. Cha-il begins reinvestigating a tower crane accident already closed to audit and visits the construction site. When he suspects evidence of corruption on the foreman's laptop, the foreman attempts to run away.

Cha-il requests to perform a special audit on Senior Managing Director Seo and Vice President Hwang. However, those selected for the audit are manipulating or running off with evidence. Therefore, he looks into the tower crane operator and finds something odd on the day of the accident.

Cha-il investigates a 3.4-million-dollars embezzlement case from a housing project and investigates Mi-kyung, the head of the Housing Team, who is his college junior. As the investigation progresses, a sexual harassment scandal occurs between them, putting the embezzlement case in turmoil. However, when Cha-il thinks he's solved the case, Hwang Dae-woong stands in his way.