The sixteenth episode of "Seoul Busters" kicks off with Yu-bin diving deep into his studies, determined to become the ultimate gang boss. Jong-ryeok catches him mimicking a gang leader's demeanor and can't shake off the worry that Yu-bin might be losing touch with reality. Furthermore, Jong-ryeok is concerned about Yu-bin's ability to go undercover, recalling how he froze up during their last mission. However, Yu-bin has moved past that incident and is ready for the next challenge.
To transform the team into convincing gangsters, Hyun-seo makes a surprise visit to give them a complete makeover. Tan-sik finds himself smitten with her, but Min-seo swiftly puts an end to his infatuation. Yu-bin secures an office nearby for the team, and after their stylish transformation, they head to their new workspace to set things up. Everyone is astounded by Yu-bin's dedication to his new role. Together, they look like hardened criminals, adorned with fake tattoos and exuding a menacing aura.
As they settle in, the team embarks on promoting their new gang on social media. However, their posts fail to attract the desired attention. Discouragement begins to creep in, but a ray of hope shines when Tan-sik spots a post on MZ Union's social media page announcing a gathering for all gangs. The team attends the bash, and Yu-bin wastes no time in spreading their name. He sends the others to mingle and gather intel on Yoon. One of the attendees offers to put in a good word for the Dongbang gang and connect them with Yoon, but ultimately, it's up to Yoon to decide whether to assist them in launching a gambling app.
Over the following days, the team's concern grows over Yu-bin's increasing immersion in his role. They also become increasingly impatient, awaiting Yoon's response. Fortunately, a few days later, Yoon drops by their office to make their acquaintance. He tasks the team with proving themselves by collecting a defaulted loan from a notorious gang.
To everyone's surprise, Yu-bin agrees to the terms. They venture out to collect the loan but soon realize they're dealing with a ruthless gang. A fierce battle erupts, but the Dongbang gang emerges victorious, securing the loan. Yu-bin calls for backup and has the gang arrested, instructing the officers to keep the arrest under wraps to avoid alerting Yoon. Impressed by their prowess, Yoon agrees to meet the team at their headquarters, a location that had previously remained elusive to the police.
The team arrives punctually, their faces etched with concern over the looming challenge. Yoon strolls in shortly after, brandishing the gambling operation's blueprint. He calls upon one of his tech-savvy teammates to unravel its intricacies. Once the briefing concludes, the team springs into action to apprehend the criminal syndicate, leaving Yoon astounded by his own inclusion in their net. Yet, Mastar remains elusive.
Luckily, Yu-bin, having meticulously analyzed Mastar's communication patterns, uncovers a crucial clue. From his communications, they cleverly deduce that he resides within the military ranks. Delving deeper, they pinpoint a specific regimen that, due to recent policy changes, enjoys expanded telephone privileges. Armed with this insight, they zero in on Mastar and Yu-bin efficiently transfers him into the custody of the military police.
Meanwhile, the remaining team members swoop down on the gang's other members, persuasive tactics in hand, encouraging them to spill the beans in exchange for leniency. Initially dismissive, treating their arrest as a mere inconvenience, the gang's members come face-to-face with the stark reality when Cheol-Yong's disheartened mother steps into the station.
As the case draws to a close, Yu-bin returns home, his mind still grappling with the stalking and kidnapping mystery Hyun-woo had brought to his attention. He is convinced that this inquiry will ultimately lead him to the perpetrator who once harmed the enigmatic woman from his past.
