Watch on Viki/Good Drama
Eun Dae Gu (Lee Seung Ki), Uh Soo Sun (Go Ah Ra), Park Tae Il (Ahn Jae Hyun) and Ji Gook (Park Jung Min) - otherwise known as the P4 - are the new recruits in the violent crime unit at Gangnam Police Station. These rookies are neither enthusiastic, nor passionate about their new jobs and have joined the crime squad for varying but unbefitting reasons. They are lead by an erratic and hot headed Seo Pan Suk (Cha Seung Won) who wants nothing more than to wash his hand off of the incompetent new recruits. This drama follows the journey of these young cops as they fumble, learn, fall in love and find their way to becoming people the citizens can trust.
[OSTs by Kwon Jin Ah & ballad version of "I'm In Love"]
source: SBS + You're All Surrounded wiki + KpopMar OST 1, 2