Episode 12 of Oasis begins with Hwang and Dong-pal discussing business. Dong-pal wants to buy and sell companies in South Korea. In return, he will contact the Kremlin and give 30% of his Korean business profits to Hwang. Happy with the results, Hwang and Cheol-woong return home. Hwang thanks him for his help but when Cheol-woong points out that he didn’t do anything, Hwang is just happy he has someone to rely on.
Meanwhile, Du-hak is upset that Dong-pal keeps postponing his journey back to South Korea. He threatens to burn down his establishments but the older man calms him down. He gives him a fake passport and also promises him 10% of his funds as compensation for his work at the gambling dens. Du-hak is also appointed regional manager of his South Korean company.
Travelling in style, Du-hak reaches South Korea and teams up with Ha-yeon but she rejects his ideas. She wants to get in touch with the NSA to get an internal analysis of weak companies and Du-hak doesn’t look happy. But Dong-pal stays true to his word and contacts the Kremlin which has Hwang overjoyed. He hints at a promotion for Cheol-woong in the NSA for bringing him the news while Captain Oh looks annoyed.
As for Jung-shin, she opens the Young Generation Film Studio with Yang-ja and Cheol-woong helping her. He even goes as far as to bring her first rights to Hong Kong films and offers to help her with a bank loan. As they head out, she thanks him for his help. Du-hak arrives and sees them together. He is about to approach them but Cheol-woong hugs her and she beats him up. Du-hak remembers their time in Yeosu and smiles.
He then goes to the restaurant run by Hyung-joo, Seon-woo and Gil-su. He is amused with the way they handle the business, rushing and taking orders and cooking. Du-hak jokes about wanting commission and they all finally notice him. They all tear up as they hug him and sit to catch up. Hyung-joo warns him not to take revenge but Du-hak points out that he will constantly be on the run till he fixes everything.
Hyung-joo is tasked with Ha-yeon’s orders so Du-hak can find out about the weak businesses. With Du-hak making him the CEO of a mysterious US company, Hyung-joo’s classmates from SNU easily help him out. Seon-woo searches for the hit-and-run driver that killed Mr. Lee. Finally, Gil-su brings back the old gang members Rotary and Wolf.
He even recruits Young-pil and Gwang-tak who have trouble letting bygones be bygones and try to fight each other. But briefcases full of cash shut them up. Du-hak tells them to open gambling houses with it as it will be the source of their influence.
Meanwhile, Yeo-jin sets up a meeting with Geum, Yeon-hee and Cheol-woong. She says she met the Geums while golfing but the whole thing amuses Oh who remembers her saying Cheol-woong needs to think the set-up is natural otherwise he will react negatively.
However, the straightforward Yeon-hee asks Cheol-woong out on a date which has him all flustered. He ends up locking eyes with Oh who smirks which makes the boy even more suspicious. He claims he is seeing someone and glares at Oh before leaving. Instead, Cheol-woong goes with Jung-shin to get her a loan. Because of his connection, she immediately gets it. He acts cocky but is genuinely happy for her.
At Lee’s office, Poong-ho is furious with the west coast landowners asking twice the money since the demand is high. As he and Mrs. Lee discuss what to do, Du-hak spots them. He suddenly sees Cheol-woong and Jung-shin arriving and taking them out for a meal and he feels confused.
He follows them to the restaurant and watches them from outside as Lee feeds Cheol-woong and Jung-shin while they call her mom. Poong-ho acts jealous and she ignores him while complimenting how good the kids look together. They all laugh while Du-hak watches them and smiles.
As they disperse, he follows Cheol-woong who drops Jung-shin home. She feels bad for taking advantage of his feelings and he jokes that she should then date him. She recalls how he and Du-hak were her biggest source of strength and he smiles as she says he is precious to her. But she ends up friend-zoning him as she says she doesn’t want to lose the friendship they have.
A brokenhearted Cheol-woong goes home only for his mother to confront him. She is humiliated that he offended a chaebol family for a girl who doesn’t even like him. He retorts that even Mrs. Lee thinks he and Jung-shin look good together but this just angers her further. She tells him to stay away from the woman and as he prods why she hates Mrs. Lee it escalates into a physical argument.
Hwang breaks them up and calms Cheol-woong down. He points out that since she is stubborn in what she thinks is right for her son unless Cheol-woong can convince her of his feelings, he should give up on Jung-shin.
He then pacifies Yeo-jin who cannot understand why he would reject a chaebol family. Hwang tells her that Geum is not angry and in fact, wants to meet her. Turns out he wants to partner up with her for her real estate business. He has access to special presale rights at one of the new towns. With the profit being 100 billion won, he wants her to buy it under her name.
She is intrigued and tells Oh to postpone the west coastal land purchase. The NSA officer is unhappy since he gave his word to the people involved in the project. He doesn’t like that she went back on her word and comes up with his own plan. He takes bribes from casinos under his protection and with the money, meets up with a hotel owner.
Cheol-woong has him followed and tells Hwang about it. He wants Oh arrested but Hwang refuses for old times’ sake and his loyalty to the family. Oh overhears and is further irritated when Hwang compromises with his son and has him relocated to a different NSA branch while Cheol-woong works as his special aide.
As for the gang, Seon-woo finally finds the hit-and-run driver Lee Yong-deuk and calls Hyung-joo and Du-hak over. Yong-deuk simply rambles that he did not kill anyone. Noticing that he is a drug addict, Du-hak tempts him with money for his drugs in exchange for the name of the person who ordered him to kill Mr. Lee.
After the incident, he drinks as he remembers his father. The next day, he prank calls Poong-ho from a nearby phonebooth till the forger is forced to rush out and confront him. Once he realises it is Du-hak he is shocked and hugs him. However, it is not a simple reunion as Du-hak tasks him with identifying all of Cheol-woong’s real estate. Poong-ho agrees but tells him to meet his mother to which Du-hak refuses.
He feels she would not be able to keep his secret as he needs to stay dead because of unfinished business. At that moment, Yeo-jin follows Mrs. Lee to the office and slaps her for meeting Cheol-woong. Lee points out that he came to meet her but Yeo-jin doesn’t care about the technicalities. She says it is her last warning and storms out as Lee tears up.
Meanwhile, Young Generation is bustling with incoming calls and new scripts. Yang-ja and Cheol-woong too start helping around as the phones keep ringing. They start drinking and relaxing as things start going smoothly and Jung-shin heads home drunk.
She walks by Du-hak who is waiting for her. He calls out to her and she thinks she is imagining him. She refuses to believe he is real till he hugs her and she looks at him. She finally realises it is him and they tear up as they hug.
Something fishy is definitely going on with Oh. He initially did seem flaky when he went behind Hwang’s back to help Yeo-jin get him. And now despite Yeo-jin telling him that Cheol-woong should not know about the Geums’ motives, Oh kept mocking him when Yeon-hee proposed which definitely acted as a catalyst to Cheol-woong’s outburst at the Paris Salon.
Well, now that Oh is a rabid dog set loose without a master, it feels that he is going to become the major antagonist in the second half of Oasis. Even Hwang seems to have mellowed down while Yeo-jin’s consequences will catch up with her soon.