Supporting
Oh Dae-hwan as Moo Gwang-il
Audit Team 3 Manager. With no standout skills, he rotated through various departments and subsidiaries. Through repeated demotions, he's gained a thorough understanding of the company's workings. He has long given up on becoming an executive, and just wants to coast and retire without incident.
Jang In-sub as Cha Seong-tae
Audit Team 3 Manager. He is a master of office politics, expertly delegating tasks and avoiding actual work. He comes up with any excuses to use the company credit card for personal purchases and does his personal business in the company restroom. He wastes most of his work hours checking stock trading screens or browsing second-hand trading apps.
Park Joo-hee as Pyeon Hae-young
Audit Team 3 Accountant. As an accounting clerk, she oversees expense processing, budget management, and departmental events like team dinners. With her backing, she wields significant control, essentially running the department's finances. She dictates budget rules beyond company guidelines, strictly rejecting expenses that could've been approved with some flexibility.
Shim Su-bin as Yoon Da-hye
Audit Team 3 Assistant Manager. With an Economics degree from Seoul National and a CPA license, she was a standout hire who chose Haemu Group over top firms, but later she seems less driven to prove herself. She is burnt out from exams and competition, and just wants to coast.
Lee Kwang-hee as Baek Hyun-kyu
Audit Team 3 Chief. He got into the company through an executive who liked his spirit, despite his lack of top credentials or a big-name school. Despite being a slow processor, he landed a spot in the Headquarters Audit Office thanks to his standout loyalty; he catered to superiors and gave his all to the company, going above and beyond on protocol.
Uhm Jun-gi as Ahn Min-soo
Audit Team 1 Manager. He is Ki-jun's colleague and friend, who is envious of his success.
Bae Jae-seong as Seong Du-gi
Audit Team 1 Chief. The youngest in Audit Team 1, he's got a cheerful vibe and a humble attitude, making him a favorite among seniors.
Kang Sang-jun as Jeon Seong-yeol
The executive director of Haemu Group, who is Jae-yeol's half-brother.
Jeon Gook-hwan as Jeon Mu-tae
The chairman of Haemu Group, who is Jae-yeol's father.
Ji Yi-soo as Oh Hyun-young
Jae-yeol's wife, who is the eldest daughter of Sesan Group.
Son Ji-yoon as Bu Se-young
The HR director of Haemu Group.
Lee Ji-ha as Ki-jun's mother
Park Ji-il as Joo In-ah's father
Park Yong-woo as young Joo In-ah's father
Yang So-min as Joo Kyeong-hee
Keum Min-kyung as young Kyeong-hee
In-ah's late mother.
