Episode 4 of "Dong Jae, the Good or the Bastard" kicks off with a haunting flashback to the moment preceding Yoo-ri's tragic demise. We witness the perpetrator pulling the trigger as her father helplessly searches for her within the confines of their home. Amidst the chaos, the police stumble upon a shadowy figure lurking nearby and apprehend Gyeo-re.
News of his arrest swiftly wings its way to Nam Wan-sung, who promptly reaches out to Mi-ran, urging her presence at the scene. However, sensing the potential for suspicion, she delegates Dong-jae to attend on her behalf, fulfilling Wan-sung's earnest request. Dong-jae arrives at the grim crime scene, where he learns of Yoo-ri's untimely death and his mind reels back to the sight of Gyeo-re exiting his residence, a shotgun cunningly concealed in a tennis bag.
Within the confines of the police station, Wan-sung's desperation is palpable as he implores Dong-jae to secure Gyeo-re's freedom, hinting at his capacity to erase all traces of the controversial land dealings and bribes. Yet, Dong-jae remains unperturbed. A contingent of officers accompanies Wan-sung in a futile search for the shotgun, which has conveniently vanished. This turn of events now entwines Wan-sung in a web of trouble for illegally possessing a firearm. Meanwhile, Gyeo-re remains stoically silent in his detention cell.
The following day, at an official meeting, Dong-jae is handed the reins of the investigation, a transfer orchestrated with seamless precision. Dong-jae's astute mind pieces together that Wan-sung's land holdings served as a covert bargaining chip to spring Gyeo-re from his plight. The police update Dong-jae on their findings, confirming Gyeo-re's handoff of the shotgun to Yoo-ri, but the remainder of the narrative remains shrouded in mystery. In a bid to uncover further clues, Dong-jae visits the proprietor of the bowling alley, yet his endeavor yields but a trickle of information.
Meanwhile, Park Chan-hyeok dishes out crucial information to Byung-jun, revealing that Choi Geum-ho is poised to receive a fresh consignment of narcotics. Elsewhere, Wan-sung crosses paths with Gyeo-re, who adamantly denies any involvement in Yoo-ri's demise. During an intense interrogation session, Gyeo-re remains tight-lipped until Dong-jae unleashes accusations against him, citing incriminating evidence from the hospital. Finally, Gyeo-re's memory flickers back, painting a picture of Yoo-ri's accidental fall at the hospital. The young duo had chance upon a stash of drugs at the train station while on an excursion to try out a novel restaurant. They embarked on a clandestine venture, peddling the illicit substances through an anonymous app. When Yoo-ri insisted on selling the remainder to an unknown buyer, Geum-ho, fearing for her safety in the escalating danger, armed her with a shotgun for protection.
It transpires that Park Chan-hyeok had pulled off a heist, snatching a significant quantity of drugs from Choi Geum-ho, thereby prompting Geum-ho's desperate hunt for the perpetrator. Yoo-ri's father stumbles upon a cache of cash hidden in her cupboard, sparking further curiosity. Dong-jae's mind drifts back to a past conversation where he had heard whispers about a mysterious disappearance of a new ecstasy variant dubbed "Purple." The lightbulb moment dawns – Gyeo-re and Yoo-ri's underground drug operation offers a plausible explanation for this abrupt scarcity. Dong-jae delves deeper, scrutinizing CCTV footage from the terminal, and catches a glimpse of Park Chan-hyeok inadvertently brushing past the two teenagers, setting the stage for an intricate tale of deceit and danger.
