Main •
Park Hae-soo as Cha Jae-hwan, 35 years old, a perfectionist homicide detective •
Lee Hee-joon as Lee Joong-yeob, a surgeon •
Claudia Kim as Eugene Hathaway, a profiler from the
FBI Supporting People around Cha Jae-Hwan •
Nam Gi-ae as Cha Eun-soo, 60 years old, Jae-hwan's mother •
Kang Shin-il as Han Joo-seok, 60 years old, head of the Violent Crimes division
Joongsan West Special investigation headquarters •
Woo Hyun as Bae Seung-gwan, 60 years old, Joongsan Police Chief • Heo Jun-seok as Go Kwang-soo, 38 years old, head of the Special Investigation Headquarters • Kwon Hyuk-hyun as Lee Geon-yeong, 29 years old, representative of a powerful team of special investigations. A young detective who is best friends with Jae-hwan. He is jealous of Eugene, former FBI agent • Yoon Ji-won as Jang Ha-na, 29 years old, an agent of the special investigation team. She is good at computers and works in an image analysis room • Kim Ji-hoon as Jo Han-cheol, 42 years old, homicide detective • Jung Young-ki as Im Pil-seong, 38 years old, homicide detective
Seo-ryun group • Kim Gwi-sun as Lee Min-ki, 64 years old, Member of Parliament •
Kim Ho-jung as Lee Hwa-jeong, 58 years old, president of Seoryun Hospital •
Lee Ki-young as Seo Hyun-tae, 64 years old, Chairman of Seo-ryun Group
Others •
Cha Joo-young as Kim Hyo-kyeong, 35 years old, an elite reporter belonging to the investigative reporting team of a broadcasting company • Lee Seung-hoon as Ham Yong-bok, a former detective who was involved in the Chimera investigation with Joo-joo and Seung-gwan, and now owns a beauty salon. •
Han Ji-wan as Ryu Sung-hee ==Production==