An ace police crisis negotiator, Chae-yoon, is called to the scene where her supervisor is taken hostage. Through the control room monitor, she is faced with the cold-blooded hostage taker, Tae-gu, whose demeanors are difficult to interpret. Against the 21-hour deadline Tae-gu has set, Chae-yoon tirelessly tries to crack the unusually calm perp over multiple video-calls. Eventually, the shocking truth begins to unveil.
Elenco: Son Ye-jin , Hyun Bin , Kim Sang-ho , Jang Young-nam , Jang Gwang , Jo Young-jin , Kim Min-sang , Han Gi-joong , Yoo Yeon-soo , Park Su-young , Choi Byung-mo , Lee Hak-joo , Lee Joo-young , E Xi-a , Lee Mun-sik .