Kang Suk-won

as Seung-gil

as Senior Detective

as Choir Member

as Teacher Suk-won

as Seung-won's Co-worker

as Head of Department Kang

as Care Worker

as Do-bin

as Reporter 4

as Machinery Team Leader

as Prisoner 1

as Behavior Examiner

as Cameraman

as Squad Member

as Taekwondo Team Coach

as Fellow Detective

as Gangneung Police 3

as police officer

as Situation room agent

as Investigator (Eps 5)

as Gear complainant

as [Babel Chemicals team leader]

as Male Talk Show Guest

as Taxi Driver

as Hyung Joon [Woo Jin's ex colleague]