The sixth episode of Shin's Project commences with Mr. Shin reflecting on the events of the day his son passed away, a tragedy that has haunted him for fifteen years. As he makes his way to visit Yun Dong-hee, he encounters Choi Chul, who still clings to the belief that there is more to Jun's demise than meets the eye.
Meanwhile, at the federal court, Philip's parents arrive to see their son and find themselves in the presence of Judge Kim. They remain oblivious to the truth about his work at a chicken shop. Later, Judge Kim rebukes Philip for getting embroiled in the illegal election shenanigans of the previous episode, urging him to return to court immediately. But Philip begs for two more months to learn and grow.
At a Buddhist temple, Madame Joo pays her respects to Jun's resting place, while Kim Young-woo waits for her outside. At the chicken shop, Mr. Shin takes a day off to mourn his son's anniversary. Si-on spends her time studying, with Philip providing her with a master list of GED questions for practice. She casually mentions that Shin took the same day off last year, but isn't curious about the reason. However, Philip is intrigued enough to delve into the events that transpired 15 years ago with Shin. Meanwhile, Shin wails over his son's demise at the playground where he lost his life. Judge Kim arrives to offer him solace.
At the police department, Kang Yeo-gyeong (Choi Chul's junior) is promoted for arresting Councilman Choi. She now joins Chul's division alongside other detectives and they embark on a real estate scam case. Before they set out, Chul's boss informs him that he knows Chul visited Yun Dong-hee and warns him to stay away from the drug addict as it was the very case that got him in trouble before.
Judge Kim arrives at the chicken shop and assigns Shin and Philip a new case where one friend is suing the other for not returning a rental deposit. Baek Seung-mu and Ko Jae-kyung grew up together at an orphanage but now Seung-mu is the landlord of the apartment building they live in and hasn't returned Jae-kyung's deposit. Judge Kim tasks the duo with mediating the case. Afterwards, Philip inquires with Kim if the playground case refers to Shin's son's demise. Kim directs him to ask Shin himself, leaving room for further exploration and emotional depth in their journey together.
Shin and Philip embark on a journey to the orphanage where the boys forged their unbreakable bond. Shin wields a disguise, posing as a journalist, while the orphanage's director regales them with tales of how the boys grew from strangers to inseparable friends. Their journey then takes them to the apartment complex where both men now reside. There, on the street, they chance upon a fiery confrontation, each man locked in a fierce embrace of fists. Separating them, they delve into the heart of the matter.
Following their departure from the orphanage, Seung-mu reached out to his mother, the woman who had left him at the shelter years ago. Their reunion was sweet, and she bestowed upon him the apartment complex. However, she retained control over the finances. Seung-mu believed her to be investing the deposits collected from tenants, unaware that Jae-kyung was set to wed and desperately needed those deposits back.
Meanwhile, Choi Chul and Yeo-gyeong pay a visit to Oh Mi-sook, a woman connected to their real estate fraud case. She is none other than Seung-mu's mother, and her name is synonymous with a veritable hoard of properties. Yet, her residence bears the signs of long-forgotten days, its doors creaking with disuse.
At the chicken shop, the group muses on how Mi-sook might be using Seung-mu as a pawn in her scam, orchestrating a grand escape with the ill-gotten gains. With Kim Soo-dong's assistance, Shin uncovers the truth about Mi-sook and her companion, Lee In-chul, a real estate broker and her accomplice in this deceitful venture. Lee operates a highly exclusive real estate circle, conning unsuspecting individuals through shrewd deals. Shin turns to Soo-dong for an invitation into this exclusive group, only to be met with the implication that he must appear as a formidable figure to be welcomed in.
As Shin crosses paths with Chairman Park at Madame Joo's bar, he charms his way into borrowing the Chairman's flashy watch and dazzling shoes. As Shin departs, a wary eye from Kim Young-woo observes him leave. The next day, Shin struts into a real estate event, adorned in the Chairman's finery, and is welcomed into Lee In-chul's exclusive VIP circle.
At Shin's behest, Madame Joo transforms Si-on into a vision in a glamorous gown. Shin dispatches Si-on on a mission to spy on Jae-kyung as he meets his mother at a cafe. Mi-sook assures him to hold off for a week, promising to reimburse Jae-kyung. However, Si-on follows Mi-sook and overhears her instructing In-chul to "cash out" and hasten their departure. Mi-sook meets In-chul at a hotel, where Si-on and Philip pose as a couple, even securing a room adjacent to theirs. But they merely pack their bags and depart unnoticed.
Poor Seung-mu comforts Jae-kyung, assuring him that his mother will soon fulfill her promise. He even dips into his own savings to give Jae-kyung a hefty sum of cash as an emergency fund. Jae-kyung then reaches out to Philip, panicking as he struggles to contact Seung-mu. They eventually locate Seung-mu in his apartment, unconscious from an overdose of pills.
Choi Chul consults a doctor with the list of chemicals, which reveal they are antipsychotic medications and treatments for drug addiction. The doctor lists a series of symptoms that would manifest if a healthy individual were to ingest them, mirroring Yun Dong-hee's erratic behavior. Yet, a scene from the glass prison reveals that Dong-hee has been secretly withholding her medication. The climax of Shin's Project Episode 6 ends with Choi Chul informing Shin that Yun Dong-hee has eluded the hospital's grasp.
