Meet the two fearless men willing to go to extreme lengths in their pursuit of a serial killer that has shaken up their quiet city:
Lee Dong Sik, a once was capable detective, is now demoted to performing menial tasks at the Manyang Police Substation. He was just beginning to settle into a peaceful life when his new superior, Detective Han Joo Won is transferred in. Joo Won is an elite detective whose father is the star candidate for the National Police Agency’s next chief. Despite his admirable qualities and high social standing, Joo Won harbours a long-held secret.
When a string of gruesome killings occurs, a pattern takes shape that is oddly reminiscent of some cold serial-murder cases from 20 years prior. Dong Sik and Joo Won team up, vowing to stop this vicious culprit in his tracks.
As their investigation proceeds, they are forced to look far deeper than what the evidence, questioning the culpability of all those surrounding the case, including their own.
Dongmakgol is a village in a remote mountain, isolated from the rest of the world and untouched by the ravages of the ongoing war in Korea. Fate brings the three fighting forces together: a U.S. fighter pilot whose plane crash-landed in the mountain, three retreating North Korean soldiers, and two South Korean soldiers who are lost.
After a grenade destroys the food storage, they decide to stay and help the local farmers. In the process, they slowly let go of their hatred for one another and build a sense of friendship. Meanwhile, the U.S. commanders believe there is a major North Korean military presence in the area where the plane went missing and plan a major air strike. In order to spare the village from complete destruction, the soldiers decide to work together to divert the attack, possibly sacrificing themselves in the process.
In the spring of 1978, Hyun Soo transfers to Jungmoon High School in Gangnam where his mother thinks the land price will skyrocket due to the development of the area. Yet, Jungmoon High School is notorious for its severe corporal punishment by teachers and power struggles between school gangs. On the first day, he gets spanked with an aluminum baseball bat for violating the school's dress code. Then, one day, he plays basketball with his classmates and brings his team a victory, which allows him to become chummy with Woo Sik, a kingpin of the school. Before long, they find out that they both are huge fans of Bruce Lee and become best friends.
After school, on the bus, Hyun Soo and Woo Sik see a girl who resembles Olivia Hussey, the most popular foreign actress in Korea at that time. Her name is Eun Ju, a senior at a nearby girls high school. Both fall in love with her at first sight. Hyun Soo is gentle and kind, while Woo Sik is tough and charismatic. Knowing Woo Sik is so different from her, she can't help but becomes attracted to him.
Hyun Soo endures the pain of his secret love for Eun Ju. However, Eun Ju and Woo Sik begin to bicker over petty things. While she's in pain over Woo Sik cheating on her, Hyun Soo sees a chance to win her heart. In the meantime, Woo Sik and Jong Hoon, a student patrol captain, get into a fight. In the duel, Jong Hoon cheats and beats up Woo Sik, who leaves school in the aftermath of his defeat. With Woo Sik gone, Jong Hoon abuses his power as student patrol captain and bullies whoever gets in his way. Hyun Soo falls into an Inferior Class, and Jong Hoon keeps bullying him. The corporal punishment and favoritism by the teachers gradually become worse. To make matter worse, Eun Ju chooses Woo Sik over him. Driven to the wall, Hyun Soo explodes. With nunchakus tucked in the back of his pants, he goes up to the roof after Jong Hoon.