The fourth episode starts with Dr. Yeo exiting the vehicle and Tae-oh noticing Gun and Ju-yeon having a conversation. Ju-yeon feels uneasy when Gun physically blocks her and Tae-oh comes to her aid. He warns that he will find a new doctor if Gun doesn’t listen, and Ju-yeon forcibly removes Tae Oh to prevent the trial from being disrupted.
She attempts to shift the conversation by inviting Tae-oh for dinner, but he redirects by suggesting she substitutes for Dr. Yeo. Naturally, she agrees and Tae-oh quickly takes off. Gun is feeling discontent and attempts to persuade her into rejecting Tae-oh. Nonetheless, Ju-yeon warns him not to overstep boundaries and inadvertently slices his face while attempting to escape. She refuses to say sorry when he mentions she’s distant and advises him to find a friendly person, but later regrets hurting Gun and wishes to make amends, only to find out he’s already left. As she is working, she notices that Tae-oh has left her a coffee, which lifts her spirits once more. However, she still can’t get over her dinner with Gun and how he sketched a heart on her glasses.
In the meantime, Gun quietly makes his way back home to take a bath. Shin comes back from his run and gets frustrated because Gun continues to borrow his clothes and use his card, and he also made his dog leave the house for growling at him. When Gun mentions his missing wallet and phone, Shin appears to be suspicious. Shin asks Guk-bong to watch Gun since Gun refuses to return to the hospital. Much to Guk bong’s chagrin, they opt to drive in a rundown car rather than one of Shin’s luxurious vehicles.
Regarding Sae-yan, she is responsible for looking after Ju-yeon’s nephew. She spends her days drinking and attempting to reach out to Shin, but she is upset that he does not answer. After watching his game on television, she leaves the house but not before assisting the woman from the neighborhood in removing the garbage. Upon Ju-yeon’s arrival, she is frustrated by Sae-yan’s welcoming attitude towards strangers and apparent inability to stand up for herself against disrespectful men, while also causing trouble for her hosts. Exhausted, Ju-yeon drifts off to sleep and fails to make it to Gun’s appointment. Upon finding out he is at the tennis court, she makes her way there.
In the meantime, CEO Hong insists that Shin wears the new sponsored shoes for the game despite the risk of getting blisters. He also warns that he will reveal the investigation if Shin ignores him. Outdoors, Hong encounters Gun, who seeks confirmation that he will secure a full-time position if he successfully convinces Shi-on to join the agency.
Despite her dislike for the agency, Shi on still wants to challenge Gun to a match. Should they emerge victorious, she will agree to sign with the agency. Gun concedes but his performance is subpar as he continuously strikes Shi-on instead of the ball. Upon departing, he notices Sae-yan furiously scribbling on Shin’s poster. He fails to identify her and surprises her by using her glasses to admire his good looks. Later on, she is removed by security for drawing on Shin’s poster.
On the other hand, Shin emerges as the victor of his tennis match, though his mother gripes about his subpar physical state. Nevertheless, he keeps the reason for his blisters from his parents, caused by the shoes Ceo Hong made him wear. Nevertheless, Ju yeon, who had reached the tennis court in search of Gun, eavesdrops on him apologizing to his mother for a poor performance. She encounters Ceo Hong and inquires about Gun, but he rudely informs her that he has departed. Shin goes to the drugstore to buy ointment, but his OCD flares up. Nevertheless, he encounters Ju-yeon who needs non-drowsy medication and accidentally drops the eggs he is carrying. He believes he is cursed as she attempts to assist him in overcoming the belief in bad luck. He believes he could potentially fail in the upcoming competition due to the high stakes – a victory means winning 100 million won, while a loss could cost him 1 billion won in terms of fans and sponsorships. Ju-yeon cannot comfort him but she attempts to engage him in his superstition-breaking habits by consuming his preferred meals. Nevertheless, it appears that there is no established procedure for this and he simply aimed to improve her energy and spirits.
Afterward, Gun treats the hospital employees except for Tae-oh at a dining establishment and spots Dr. Yeo donning a gold Eiffel Tower pendant. Nurse Song reveals her Eiffel Tower keyring is gone, causing Gun to cough suspiciously, proving he took it for Ju-yeon.
After having dinner with Shin, she is moved by him but advises him to prioritize his own needs as well. She informs him that he performed admirably, and he is pleased. He begins jogging alongside her taxi because he needs to log his running hours while also wanting to keep her company on her way back to the hospital for her night shift. She is amazed that he arrives at her stop just as the taxi pulls up. She cleans his face of dirt and encourages him before his last game.
His joy is quickly extinguished when he receives notifications of Gun spending a few thousand dollars on food and proceeds to call him in order to scold him. He unexpectedly recalls Ju-yeon’s keychain and shouts for her when Gun tackles him because he was actually right behind Shin. He insists that the key ring belongs to Nurse Song, grabs it, and that he pranked him by tackling him to the ground as they did when they were children. However, both siblings ultimately find themselves prone on the ground. An elderly man spots them in each other’s company and assumes they are in a romantic relationship. They attempt to resolve the confusion, but the man has already departed. Later on, they reflect on their dreams and childhood memories.
Gun is feeling upset about his declining tennis skills, but Shin assures him that he will help Gun improve and achieve his tennis dreams. However, Gun advises him to pursue his own aspirations. When they were young, Gun desired a cloud and Shin imitated his sibling. Gun asserted that Shin can have ownership of all the clouds and the sun, while he is entitled to a star. Currently, Gun aspires to pursue his own dream while maintaining boundaries, and it was Gun, not Tae-oh, who delivered coffee to Ju-yeon. The two siblings begin arguing about stepping over the boundary.
At the same time, Mrs. Kyung, Ju-yeon’s mother, has started working part-time and is injured while trying to avoid Ju-yeon because she does not agree. Sae-yan is curious about why Ju-yeon is now distant despite her kindness in childhood. Mrs. Kyung reveals that her late husband, who used to work long hours, was killed by one of his own patients. Ju-yeon discovered him and now she also doesn’t want her to work part-time. Despite her cold demeanor, she possesses a kind heart.
Gun wakes up and notices a band aid covering the cut on his face. After observing Cha Shi-on’s practice, he comes up with a new idea. By getting Guk Bong to impersonate him, he successfully flees the hospital. He gets Shi-on to sign a contract with him and he quits Hong’s agency, leaving him stunned. Gun has indeed launched his very own agency, which is called GOON. Hong risks revealing Shi-on’s injury, but Gun beats him to the punch by already leaking the news.
In the meantime, Ju yeon and the hospital board are enthusiastic about the successful trial, but they require the trial-supporting documents from the UK doctors before providing full funding. We return to the missing suitcase situation as Ju-yeon acknowledges that her bag with important documents was never returned by Gun.
Gun does not remember the suitcase, Shin is preoccupied with his exams, and their parents are watching from the crowd. Ju-yeon fakes a request for Gun’s ID and secures Mrs. Lee’s approval to retrieve it from their home.
During the game, Shin remembers the advice Ju-yeon and Gun gave him about prioritizing himself, causing him to make a mistake on the final serve. He continues to win while his mother emphasizes the importance of practicing more. However, he chooses to return home, greatly disappointing her. Upon his arrival home, he discovers Sae-yan at the gate, waiting for him.
Ju-yeon is inside the Lee house, searching for her suitcase. Upon entering Gun’s room, she observes its mediocrity compared to the rest of the house and sees that he has only photos of his grandparents. Finding her suitcase, she dashes out just as Gun walks in.
This episode is nice but the chemistry between Shin and Ju yeon is giving. The show should redirect it back to Gun because Ju yeon is just being awful to him at this point. Anyway, it will be nice to see what happens especially now that Goon has his own agency and his relationship with his brother seems to be better.