P4: are the new recruits in the violent crimes unit at Gangnam Police Station. The journey of four young cops as they fumble, learn, fall in love and find their way to becoming people the citizens can trust.
Lee Seung-gi
Cha Seung-won
Go Ara
Ahn Jae-hyun
Oh Yoon-ah
Seo Yi-sook
Lee Yi-kyung
Im Won-hee
Park Jeong-min
Moon Hee-kyung
Lee Ki-young
Song Young-gyu
Son Hee-soon