While he is enjoying his delicious dessert, Sunwoo, a high-ranking enforcer,
is informed that there is some trouble brewing up downstairs. Before going downstairs, he takes
one of his associates, Mingi, with him. Sunwoo finds three men in the nightclub and politely
asks them to leave, as they have overstayed their welcome at the club and have been staying beyond
working hours. When they don’t respond, Sunwoo warns them to leave before his count to three.
Not moving even in the slightest, Sunwoo orders Mingi to close the door. A huge brawl breaks out,
but Sunwoo is able to put those men down with his strong combat and athletic skills. Sunwoo
closes the hotel and tells his boss, that he would send the hotel's generated revenue to him
in the morning. Sunwoo sits down for dinner with his boss, Mr. Kang, and they both talk about the
incident that took place in the nightclub. Kang is happy with Sunwoo as he states that he handled
the situation pretty well. Kang explains to Sunwoo that those were the men of Baek Dae-Sik, with whom
they are having business tensions at the moment. Another employee of Kang, Moon Suk, arrives and
informs that the men in the nightclub were local and not of Baek. Moon Suk’s unsophisticated manner
of eating disgusts Kang, who later orders Moon Suk to leave and wait for him outside. Kang is
looking forward to fixing things with Baek’s father. Kang now reveals the real reason for
calling Sunwoo. He says that he is dating a younger woman, Heesoo, and he suspects that
she might be looking for someone else behind his back. Kang is leaving for Shanghai for a business
meeting and he orders Sunwoo to find out if his girlfriend is actually cheating on him. If she is,
then Sunwoo is ordered to call Kang immediately or finish her and her other boyfriend off himself.
Before leaving, Kang also says that he believes that Sunwoo has never been in love, which is also
the reason for him being selected for this job. The next morning, Sunwoo arrives at Heesoo’s house
and hand delivers her a present given by Kang. She opens up the present, and while she’s doing it,
Sunwoo is attracted to her elegant beauty. She finds that Kang has gifted her a funny-looking
lamp. Sunwoo informs Heesoo that Kang has ordered him to drive her to work today. Heesoo rejects the
offer and tells Sunwoo that she can go herself. As Sunwoo insists more, Heesoo says that she will
inform Kang about this. As Sunwoo covertly waits outside Heesoo’s house, he discovers a young man
arriving at her house and leaving with her. He follows them to a restaurant where they
have dinner together. He later follows them to a nightclub, where they dance extremely close to
each other. When the young man drops Heesoo at her home, Sunwoo receives a phone call from Moon Suk,
who tells him to come to the hotel soon. Moon Suk tells him that Sunwoo should be dealing
with Baek’s men. Moon Suk receives a call from Baek which Sunwoo answers and tells Baek to meet
him face-to-face if there’s any problem. Sunwoo hangs up the call and Baek feels disrespected.
When one of Baek’s men secretly chuckles at what has just happened, Baek beats him up with the
telephone badly. Moon Suk lets Sunwoo know that his behavior has made their problems even worse,
but Sunwoo doesn’t bother as he believes that it was Moon Suk’s job to handle in the first place.
Sunwoo goes back home and after taking a shower, he begins to think of Heesoo before going to
sleep. The very next morning, he gets a call from Heesoo who asks for his help and tells him to meet
her. Both of them have lunch together and Heesoo tries to start a conversation with him. She lets
him know that Kang has told her that Sunwoo is actually a scary man. Sunwoo tells her there’s
nothing like that. Heesoo asks him if he’s an enforcer. Not wanting to disclose his actual
profession, Sunwoo tells her that he just works at the hotel. After having lunch, Heesoo goes to
a lamp store where she comes across a beautiful lamp, but doesn’t buy it as she can’t afford it
at the moment. Sunwoo tries to ask Heesoo why she is dating Kang. Heesoo, in turn, asks him why he
is trying to ask her a question like that. Sunwoo tells her that it’s perfectly fine if she doesn’t
want to answer his question. Heesoo leaves for her music recital and tells Sunwoo that she can
take a taxi back home. While her recital is being recorded, Sunwoo looks at her and is even more
attracted to her beauty now. Mingi informs Sunwoo that Moon Suk is looking for him. Sunwoo goes to
the hotel and finds Moon Suk having a good time with Baek. Sunwoo isn’t thrilled to see Baek in
the hotel. Baek apologizes to Sunwoo for being rude on the phone, and classifies it as nothing
but a misunderstanding. Sunwoo doesn’t believe him and tells him that there’s no misunderstanding
between them. He lets Baek know that he should stop using his men to mess with him. Moon Suk gets
furious over Sunwoo's rude behavior, and before things could heat up even more, Sunwoo leaves.
Sunwoo goes to pick up Heesoo and before he could reach her, he finds her secret lover coming and
picking her up from work. Heesoo is dropped back at her home and the young man leaves soon
enough. Heesoo has observed that Sunwoo has been following her stealthily, and as Sunwoo leaves,
she calls her secret boyfriend back. Her boyfriend drives recklessly and almost gets into an accident
with Sunwoo. While driving back home, Sunwoo remembers that Heesoo’s boyfriend had passed by
him and returned to her. Sunwoo hastily returns to Heesoo’s home. He secretly enters her house
and finds both of them red-handed. A furious Sunwoo begins to beat up Heesoo’s boyfriend.
The young man tries to get an upper hand, but Sunwoo’s combat skills are no match for him.
Before Sunwoo could finish the young man off and call Kang, he observes Heesoo’s true love for
her secret boyfriend. Not wanting to inflict any kind of trouble in Heesoo’s life, he decides not
to inform Kang. He gives Heesoo and her boyfriend another chance at everything. He tells them to not
see each other from this day forward and forget that any of this actually happened. Heesoo’s
boyfriend leaves and Heesoo is upset. She tells Sunwoo that it would be actually difficult for
her to stay away from her boyfriend. While driving back to his apartment, Sunwoo finds a group of men
chasing after him, and spitting alcohol on his car while they are on the road. Sunwoo speeds
up and is able to stop that group of men. He severely beats up those guys before leaving.
When Sunwoo reaches the underground parking lot of his apartment building, he feels as if someone
is around him. He yells that if someone is there then he should show himself. A mysterious man,
who is wearing a cap, appears and tells Sunwoo to apologize for his actions. Sunwoo assumes that the
mysterious man might be Baek’s guy. The mysterious man asks him to admit that he was wrong and that
nothing bad would happen to him. Sunwoo tells him to go away and doesn’t apologize. Kang returns and
the first thing he does is meet Heesoo. She is a bit anxious as she’s afraid that Kang might
have found out about her other boyfriend. Kang tells her the reason that he likes her so much,
is that she doesn’t care what other people think about them, which is why Kang is always excited to
meet her. Sunwoo goes to a shop to buy some beers. When he is in his apartment, a drunk Sunwoo finds
three men who beat him up badly. The mysterious man arrives to give Sunwoo a final blow before
taking him. Sunwoo is tied up and is in a horrible state. Baek arrives with his man who taunts Sunwoo
even more. Baek prepares his men to end Sunwoo once and for all. Sunwoo is scared to death, but
luckily for him, Baek receives a phone call and is ordered to drop Sunwoo at a distant location.
Sunwoo meets Kang and the rest of his man. Kang has found out that Sunwoo didn’t reveal Heesoo’s
affair with another man to him. Kang asks Sunwoo the reason for not telling him. Sunwoo remains
silent and a disappointed Kang leaves. Moon Suk and a bunch of Kang’s men remain with Sunwoo. Kang
calls Moon Suk and is told to put Sunwoo on phone. Kang asks Sunwoo one last time why he didn't
inform him about Heesoo’s affair. He responds that he thought if Heesoo would forget about
her boyfriend then everything would have been normal. Kang asks if he has feelings for Heesoo,
but Sunwoo doesn’t answer the question. Kang orders Moon Suk to torture Sunwoo. Moon Suk and
other Kang’s men try various ways to torture Sunwoo, even burying him in the ground at one
point. When Sunwoo comes out of the hole, he was buried in, he is washed up and given a cell
phone. He is told by Moon Suk that he has fifteen minutes to fix his mistake and make everything
alright. Sunwoo is furious at Moon Suk and tells him that he should never play with someone’s life.
Sunwoo observes every man around him and tries to plot the best possible way to
escape everyone. Moon Suk finds Sunwoo talking to someone on the cellphone. Thinking that he
might have apologized to Kang, Moon Suk takes the phone and sees that it has no battery in
it. Sunwoo has taken out the battery and uses it to attack Moon Suk. A long fight ensues,
and Sunwoo attempts to beat up anyone that comes near him so that he can escape successfully. He
is able to fend off the majority of men and is also able to steal a car which allows him
to leave immediately. Kang gets upset after he finds out from Moon Suk that Sunwoo has escaped.
Kang meets with Baek and his other associates as well. Kang informs them about Sunwoo and how they
all need to be together in finishing him off. Kang also shares his mindset from a boss’s perspective,
as he believes that a person has to listen to his boss even if he is wrong. Mingi receives
a phone call from Sunwoo, who is told to deliver him something to a construction
site. Both of them meet in that place, and Mingi asks if Sunwoo is doing fine. Sunwoo
lets him know that he is looking forward to finishing everything off. Meanwhile,
Kang receives a call from President Won, who tells him that it’s foolish for Kang to go after
Sunwoo as it doesn’t suit his reputation. Kang still believes that he has to finish off Sunwoo,
who is looking at him from a place nearby. Sunwoo delivers a gift to Heesoo at a place where she
is currently residing. Sunwoo goes to a remote location, where he meets two guys in an attempt
to buy a gun. The two men ask for money first which Sunwoo provides with ease. One of those
guys asks him the reason for buying a gun from them, but Sunwoo believes that he doesn’t have to
answer everything as money is the only thing they asked for. Both of the arms dealers argue with
each other, as one of them believes that Sunwoo might be an official and could put them in jail.
The two men tell Sunwoo to meet them tomorrow, and should also bring a guy who could vouch for him,
so that their deal can be finalized. As the two men leave, they crash their car nearby.
Sunwoo meets the head of those arms dealers. The head asks Sunwoo about the person who referred
them to him. Sunwoo tells him that a person, named President Han, told him about those arms dealers.
The head of the arms dealers asks Sunwoo why Han needs a gun, to which Sunwoo responds that he’s
only there to pick it up and doesn’t know the specifics. The head finds Sunwoo suspicious of
something and asks about Sunwoo’s real profession. Before handing him the gun, the head tells Sunwoo
that he has to confirm this from Han, and only then can Sunwoo leave with the gun. While they
are waiting for Han’s call, the head of the arms dealers shows Sunwoo how to assemble and dissemble
a gun. The head of the arms dealer soon gets a call from han, and he is informed that he doesn’t
know about Sunwoo. Realizing that his lie has been caught, Sunwoo quickly assembles the gun he was
handed and shoots the head of the arms dealer. He proceeds by shooting one of the arms dealers and
chases after the other one in the hallway. After finishing off the other one as well, Sunwoo drags
him back to the apartment and gathers all of the guns before departing. The brother of the head of
the arms dealer tries to call him, but he leaves him a voice message that he is coming to meet him.
Sunwoo goes back to the city and holds the mysterious man, who threatened him
in the parking lot, at gunpoint. He commands that man to call Baek. Soon,
the brother of the head of the arms dealer arrives and observes the chaos that preceded
his arrival. He finds the card that Sunwoo left there. He packs guns for himself and leaves to
find Sunwoo in order to avenge the death of his brother. Baek has been told to reach an ice rink,
but much to his shock, Sunwoo arrives as well. Knowing everything Sunwoo has gone through,
Baek tries to pretend that nothing ever happened. Sunwoo asks Baek why did he put him through so
much pain. Baek tries to end the conversation and while doing so, he takes out a knife from his
pocket and attacks Sunwoo multiple times. Sunwoo almost loses consciousness and Baek begins his
taunting as usual. As Baek moves forward toward him, Sunwoo takes out his gun from the bag and
shoots Baek. Even with being shot multiple times, Baek tries to run for his life but to no avail,
as Sunwoo is able to put him down for good this time. Sunwoo gets in the cab and the taxi driver
asks him about the gun sounds which Sunwoo tells him not to worry about. Sunwoo tells
the taxi driver to take him downtown. Sunwoo calls Kang and warns him that he has messed
with the wrong guy and that Sunwoo is coming for him. The rest of Baek’s men find the mysterious
man hung up just like Sunwoo was in the past. The mysterious man tells the rest to call Baek
and inform him about Sunwoo, but none of them are aware of the fact that Baek is no longer around.
Mingi sits down with Kang and Moon Suk, where he is asked if he has seen Sunwoo ever since he
escaped from them. A Terrified and hesitant Mingi denies seeing Sunwoo or meeting him.
Kang gets annoyed even more now as he is constantly being lied to. He pushes
Mingi’s head onto the table. Heesoo is going back to her home from work and she notices
that Sunwoo has given her a missed call. Kang has instructed his men to clear the hotel of everyone,
including the workers. Sunwoo arrives at the hotel and, at one point, also crosses
the brother of the head of arms dealers. Heesoo returns to her home and is presented with the
gift Sunwoo left for her. She opens it up to find the same red lamp she came across at the
mall and the one she couldn’t afford. Before leaving to confront Kang, Sunwoo loads up his
guns and looks at the wound that was inflicted on his body by Baek. Sunwoo takes a look at
himself in the mirror and thinks of what he has become. Moon Suk finds Sunwoo in the hallway and
gets shot by him multiple times. Before putting him to rest, Moon Suk tries to beg for mercy,
but Sunwoo doesn’t spare him. Baek’s men arrive at the hotel with the motive of ending Sunwoo’s life.
Sunwoo fights off anyone who tries to get in his way. He finally reaches the nightclub where he
meets Kang and the rest of his associates. Sunwoo holds a gun in Kang’s face and asks
for a clear reason behind him being tortured to death. Kang answers that Sunwoo insulted him,
but Sunwoo believes that this cannot be the reason. Sunwoo gets emotional and breaks down
crying saying, that he served Kang for seven straight years and he was treated like a dog
in the end. He asks Kang one last time about the real reason and when he fails to answer,
Sunwoo shoots him. Baek's men break in, they shoot Sunwoo and a huge shootout takes place.
Every associate of Kang has been put down. Sunwoo is badly injured and is unable to fight anymore.
Before they could get to him, Sunwoo is able to gather more strength and is able to finish off
Baek's men. The brother of the arms dealer's head arrives and he shoots every single man in his way
as well. He finally meets Sunwoo, who is planning on calling Heesoo. Sunwoo remembers the time he
observed Heesoo's beauty and how he was attracted to her. Sunwoo realizes that he did have feelings
for Heesoo. The brother of the arms dealers shoots Sunwoo and before he could depart this world,
Sunwoo remembers how he was always ready to fight anyone and serve his boss Kang.