“Special Affairs Team TEN” is a criminal investigation unit that tackles the most violent crimes in South Korea. These crimes usually have less than a 10% rate for arrests. They chase the most notorious killers who attempt to commit the perfect crimes.

Yeo Ji Hoon (Joo Sang Wook) is former top-notch detective, but now works as a professor. He then becomes the leader of Special Affairs Team TEN. Yeo Ji Hoon will lead this special crime unit.

Baek Do Sik (Kim Sang Ho) is as good-natured veteran detective. He possesses a keen sense of intuition, which he honed from his many years as a detective.

Nam Ye Ri (Jo An) has been a detective for 4 years. She joins Special Affairs Team TEN because of her psychological reasoning powers.

Park Min Ho (Choi Woo Sik) is a new detective. He joins Special Affairs Team TEN after impressing Professor Yeo Ji Hoon with his reasoning power.