The story starts with Shim Changmin fighting with other prisoners and snatching a bracelet that he holds dear.

The scene changes to a man in a toilet, using drugs and then murdering the bar owner. He is revealed to be 'Uknow', also known as killer cop Inspector Jung Yunho. He suddenly gets a call from Changmin who informs him of another upcoming murder. The story then shifts to five years in the past.

After meeting at a rave party in Goa, Shim Changmin from South Korea and Cho Kyuhyun from London run away together after the party becomes chaotic, due to which the police intervene. After sharing an intimate moment, they decide to embark on a journey away from their family and friends to live a life unshackled like vagabonds.

The scene then shifts to five years later, during a Christmas dinner party where a seemingly honest cop, Lee Jonghyun finds out that his wife, Minhyuk is having an affair with another man. He leaves the dinner party and gets a call from the office, informing him about a murder. Jonghyun learns that the victim is Victor, a good friend/coworker of his, and he goes to investigate further. He meets Inspector Yunho and talks to him, who disagrees with Jonghyun since he wants to kill the murderer, while Jonghyun wants to catch and imprison the murderer.

Changmin and Kyuhyun are shown in flashbacks happily living the life of vagabonds, along with the help of a friend, Jessica, who had previously come to Pattaya before becoming a drug addict and a e to earn money for buying more drugs.


Over time, Changmin and Kyuhyun fall for each other and Kyuhyun finds out one day that she is pregnant with Changmin's child, but doesn't inform Changmin.


Inspector Yunho is seen talking on the phone with his daughter Irene, but he hangs up after finding out that she is at a rave party. Inspector Yunho gatecrashes the party. Irene is shot during the crossfire. Yunho is heartbroken and indulges in drug addiction and becomes a cop who has no mercy toward criminals.


Kyuhyun, who was also at the same rave party, sees Irene getting shot and Yunho's outburst of grief and tells Changmin that she is pregnant and will not abort the baby.


The next morning, Changmin leaves Pattaya and continues his journey.


At the end of the flashback, Jessica is helping Changmin, and he kills another cop . He also claims the life of his next target Seungri in a football stadium.

As the police were on the way to the stadium, Jonghyun sees Jessica and follows her. Realizing that Jonghyun is following her, Jessica tries to burn the evidence. Jonghyun sees that he is also one of those on Changmin's Hit-List.


Changmin later surrenders himself to the cop.


In a parallel story, in the past, Jonghyun was abused by his mother who used to hit him, while his father used to hit his mother. Due to the physical abuse he endured, he started feeling unease ually. Jonghyun is about to marry Minhyuk and feels uncomfortable when she suddenly touches him. Later, he gets frustrated when his friends talk about having ual experiences would make him a man and not knowing so would make him 'less than a man'. He goes to Jessica's house as she was a e.


Unknown to him, Kyuhyun has been living with Jessica after Changmin left. Jonghyun tries to Kyuhyun and at that moment Changmin returns realizing his mistake and that he loves Kyuhyun, intervenes and knocks out Jonghyun and calls the police. Jonghyun's friends, Seungri, Dean and Victor come to investigate and take Kyuhyun and Changmin in the police van to the station.


At that moment Changmin and Kyuhyun reconcile, and Changmin promises to never leave her and their child ever again.


Jonghyun wakes up from his unconsciousness. Jonghyun plots to frame both of them for drug peddling. However, Jonghyun injects a lethal dose of a heavy drug to Kyuhyun in order to kill her and then throws her from the bridge.


Changmin was also injected drug by Seungri and sentenced to 5 years in jail. Still shocked by Kyuhyun's death, he prepares himself to seek revenge.

In the present day, Jonghyun confesses his crimes to Changmin and that he also killed Jessica as he felt he was a man when he was killing her and instigates Changmin into a fight with him and cunningly makes Inspector Yunho plan his encounter.


However, before going Jonghyun says something to make him realize that he is the last target.


Inspector Yunho takes Changmin to the same Bridge where it all started to kill him, and Changmin tells him Jonghyun and his friends killed the only family he had.


Jonghyun goes to home and sees that his wife is about to leave him and elope with Yonghwa, the man she is having an affair with. Jonghyun develops a psychotic steak and plans to murder his wife and frame Yonghwa for the crime. He closes his hands around Minhyuk's throat and begins to choke her. When he is about to strangle Minhyuk to death, he is suddenly injected with something.


When he turns behind, a person stands, wearing the same Red Hoodie Changmin had worn. That person is revealed to be Kyuhyun, who fortunately survived the fall due to Jessica as she saw her being thrown off from the bridge. However, the baby couldn't survive.


Over the course of 5 years, Kyuhyun had been planning for revenge and coincidentally Changmin had been preparing himself for the same. The murders were committed by both Kyuhyun and Changmin to seek vengeance for the death of their unborn child.


Inspector Yunho reluctantly releases Changmin as there was no evidence found against him.

The story concludes with a happy ending. Kyuhyun and Changmin, reconcile, find peace and start a new love life.