Na Jung Sun and the VIP management team of the Sung Un Department Store work hard to satisfy the VIP customers. Junior Assistant Song Mi Na works also hard but it's not easy to be a parent at the same time. Manager Lee Hyun Ah reinstates and a new employee is assigned to the team. After a long day, Jung Sun receives a strange text message about her husband, Park Sung Jun who is also the head of the VIP team.

Jung Sun starts to suspect Sung Jun of cheating on her after she got the strange message. Sung Jun often gets phone calls from Assistant Manager Cha late at night, and things happening around Jung Sun make her doubt Sung Jun more. The VIP team begins the inspection on the concierge services and finds out cases of illegal use of VIP services.

Jung Sun catches Sung Jun lying at the hotel. Sung Jun tells her that's it's all over but Jung Sun falls into a great shock by the fact that he really betrayed her. From then on, Jung Sun can't stop doubting everyone. She goes frantic with distrust and tries to figure out who Sung Jun was seeing. Mi Na leaves the office for the meeting as soon as Sung Jun also leaves for the other meeting, but Jung Sun realizes there are no meetings today.

Yu Ri takes charge of the leaflet draft but after the meeting with another team, she hears another team's Deputy head talking bad about her. Jung Sun tries to act as usual with Sung Jun but she feels lost and broken inside. The loan sharks visit Hyun Ah and threaten her until she can reach her mother. Jung Sun tracks down the person who sent the text message about Sung Jun and she gets an unexpected result.

Jung Sun is shocked at finding out that Sung Jun has been cheating on her. She refuses to talk to him at home. And she thinks that she shouldn’t have followed him to the hotel that night. Meanwhile, the VIP Management Team has given a new project that involves a popular online video content creator.

Sung Jun tries to explain that it was like an accident and begs Jung Sun for a second chance. Jung Sun keeps thinking that Mi Na could be the woman and even tails Mi Na. Meanwhile, Hyun A runs into the man who flirted with her in the hotel elevator the other day.

Sung Jun catches Hyun A in the act and decides to let her off the hook, but Jung Sun sees the two together. Jung Sun’s mind begins racing, thinking that the text message is referring to Hyun A. Meanwhile, Sung Jun receives a call from his mother-in-law and goes to meet her.

Jung Sun is shocked at finding out that Sung Jun has been cheating on her. She refuses to talk to him at home. And she thinks that she shouldn’t have followed him to the hotel that night. Meanwhile, the VIP Management Team has given a new project that involves a popular online video content creator.

Sung Jun catches Hyun A in the act and decides to let her off the hook, but Jung Sun sees the two together. Jung Sun’s mind begins racing, thinking that the text message is referring to Hyun A. Meanwhile, Sung Jun receives a call from his mother-in-law and goes to meet her.

The Marketing Team suggests a new marketing campaign targeting VIP clients, but the VIP Management Team doesn't think it is a good idea. Jung Sun comes up with a plan to dissuade the Marketing Team without butting heads directly. Meanwhile, Jung Sun meets with Hyun A to offer some help financially and ends up telling her about Sung Jun’s affair.

Jung Sun goes to see her mom at the hospital. Sung Jun and Jung Sun’s dad try to be friendly, but Jung Sun’s attitude toward her mom is cold and resentful. Meanwhile, Daniel, the chairman of a luxury jewelry brand called Tifone, visits Korea unexpectedly. It’s up to Jung Sun to secure a contract with Tifone, despite Myungil Department Store’s interference.

The story of Sungwoon Department Store's team who works for VIP clients which constitute 1% of their customers. One day after a receiving a text message of her husband's infidelity from an anonymous source Na Jeong-seon begins to suspect her husband and her colleagues of having an affair. In her quest to discover the truth, she ends up revealing more than one secret that her colleagues are hiding.

Each backed by rivalling conglomerate heirs, Jung Sun and Sung Jun go head-to-head as leaders of a new task force.

V.I.P. is an office mystery drama about the rise of working women as they run into troubles at work and in their personal lives, but endeavor to get back up and move forward again. Park Sung Joon is a team leader of VIP department store department. After graduating from a prestigious university, Sung Joon entered the company and now has the ability, the opportunity, and ambition. Park Sung Joon's wife, Na Jung Sun is a strong woman with a bright personality, but most people are unaware of her struggle.

Sung Jun and Vice President Ha are eventually forced to leave the company after President Ha’s victory. Yu Ri also decides that she has to let Sung Jun go after admitting how her presence reminds Sung Jun of Jung Sun. Sung Jun visits Jung Sun at her house and shares his thoughts on the past years of life with Jung Sun. After exchanging words of understanding, both cheer each other for a new beginning.

Sung Jun is slightly injured while helping the chairwoman of Hanjeong. Jung Sun asks him to answer her questions about his affair and he says they should talk after the event. Meanwhile, a group of VIPs recognizes Yu Ri and tease her a bit. The vice president’s wife takes things further and humiliates her in front of the whole crowd. On his way to meet up with Jung Sun, Sung Jun receives a text message.

Sung Jun is slightly injured while helping the chairwoman of Hanjeong. Jung Sun asks him to answer her questions about his affair and he says they should talk after the event. Meanwhile, a group of VIPs recognizes Yu Ri and tease her a bit. The vice president’s wife takes things further and humiliates her in front of the whole crowd. On his way to meet up with Jung Sun, Sung Jun receives a text message.

A video clip of Yu Ri being drenched in wine at the Tifone event gets leaked to the press and the internet begins speculating about Yu Ri’s relationship with the Vice President. Jae Woong holds an emergency press conference and Yu Ri’s identity is revealed. Meanwhile, Jung Sun continues digging for the woman Sung Jun is seeing.

Vice President Ha throws a dinner in celebration of the successful Tifone event and Sung Jun’s promotion. After that dinner, preferential treatment for Yu Ri begins. As Jung Sun becomes the temporary acting director for the VIP Management Team, she has to follow orders from the Vice President to give Yu Ri an assignment.

Sung Jun recalls how he first connected with Yu Ri after his father’s funeral. Meanwhile, Mi Na goes to the hospital for her abortion and Hyun A moves into the house where Yu Ri used to live. At a dinner with Vice President Ha, Jung Sun delivers shocking news with a photograph.

Jung Sun is reminded of the time when she suffered a miscarriage and how Sung Jun behaved at that time. Meanwhile, upon a VIP customer’s request, the VIP Management Team has to hold a grand birthday party for a young girl. Everything seems to go smoothly at the party in the woods, but Jung Sun hears that the birthday girl has gone missing.

The vice president orders HR to transfer Jung Sun to another branch. Hyun A advises Mi Na that she should keep the distance from Mr. Bae. Mi Na ignores the advice, but she and her husband end up in trouble with Mr. Bae. Meanwhile, Yu Ri’s mom passes away, and she’s in deep grief. Then she calls Sung Jun in the middle of the night.

Jung Sun suggests that Jae Woong revoke the decision about transferring her to another branch. She makes it clear that her action is nothing but a protective measure. Meanwhile, Hyun A decides to go public on the Bae Do Il’s sexual harassment from a year ago, which may affect dearly on the company’s reputation.

An employee from the HR department approaches Hyun A to persuade her to stop the public disclosure of Bae Do Il's sexual harassment. However, Hyun A decides to go all-in with it to prevent further victims. Hyun A brings a written complaint directly to Bae Do Il and takes her first step toward the war against the company. Meanwhile, Jung Sun finds out that the strange text about Sung Jun’s affair was from Yu Ri.

Yu Ri explains her actions to Sung Jun when Sung Jun asks why she sent the text message to Jung Sun and she also hopes that Sung Jun won’t leave her. Meanwhile, Do Il gets fired from the company for his wrongdoing. Mi Na feels tired after going through a series of stressful events and she considers quitting the job to stay home and look after the boys. Yu Ri tries to explain the reasons behind her actions to Jung Sun. Meanwhile, Yu Ri becomes the Chief of the Prestige Team.

After finding out that there has been an official promotion for Yu Ri as the Chief of the Prestige Team, Ms. Ha suspects that this is Vice President Ha's idea to take control over the most influential team in the company. Jung Sun comes up with a counterstrategy to go against Vice President Ha's takeover plan and decides to support Ms. Ha.

As Jung Sun decides to support President Ha, she is ordered to work on the new project alongside Yu Ri and this signals the official battle between President Ha and Vice President Ha. Meanwhile, although the case regarding Do Il has been resolved for Mi Na, she decides to quit the job and submits her resignation letter to Jung Sun.

When Sung Jun asks Jung Sun to stop the meaningless fight, she refuses and rather warns Sung Jun that she will make sure she wins this fight. As the battle between President Ha and Vice President Ha continues, Yu Ri feels left out among her new family, making Yu Ri feel more dependent on Sung Jun. Eventually, Sung Jun tells his mother about his plans on divorcing Jung Sun.

As Sung Jun and Jung Sun get ready for the charity event regarding the launch of The Black Society, Sung Jun accidentally arrives at Jung Sun’s house after drinking heavily with the Vice President. When Yu Ri calls to check up on Sung Jun, she finds out that the taxi driver dropped Sung Jun off at K Hill in Hannam-dong. This eventually triggers Yu Ri’s jealousy and she feels anxious about the whole situation.

Jae Woong tells Yu Ri to study abroad as soon as the charity event is finished. Jae Woong also tells her that Sung Jun will be transferred so that she can be with him while she’s abroad. Knowing this, Yu Ri feels she has to do something to rush Sung Jun’s divorce. Meanwhile, Lee Su Jeong of LN Foundation appears at the charity event. By the end of the charity event, Jung Sun gets into a hassle that might expose Sung Jun’s feelings.

Jae Woong tells Yu Ri to study abroad as soon as the charity event is finished. Jae Woong also tells her that Sung Jun will be transferred so that she can be with him while she’s abroad. Knowing this, Yu Ri feels she has to do something to rush Sung Jun’s divorce. Meanwhile, Lee Su Jeong of LN Foundation appears at the charity event. By the end of the charity event, Jung Sun gets into a hassle that might expose Sung Jun’s feelings.

Sung Jun and Vice President Ha are eventually forced to leave the company after President Ha’s victory. Yu Ri also decides that she has to let Sung Jun go after admitting how her presence reminds Sung Jun of Jung Sun. Sung Jun visits Jung Sun at her house and shares his thoughts on the past years of life with Jung Sun. After exchanging words of understanding, both cheer each other for a new beginning.