The second episode of "Buried Hearts" unfolds with Eun-nam meticulously preparing for her wedding day, when Il-do enters the scene, revealing a pivotal backstory. Eun-nam is unveiled as the daughter of Deok-hui and her late first husband, whose tragic demise occurred in an accident that also involved Il-do, their close friend. Il-do confides that he and Eun-nam's mother are aware of her affair with Dong-ju, prompting him to inquire whether Dong-ju could pose an issue. She assures him that Dong-ju is not the possessive type.
Cutting back to the wedding festivities, Dong-ju is abruptly removed and confined to a cramped room. He receives a premeditated text from Eun-nam, urging him to seek revenge by moving on with another woman, insisting that she deserves it. Following a brief exile, Dong-ju is conditionally reinstated to his wedding duties, on the condition that he causes no disturbances. When he confronts Eun-nam, his words are filled with venom as he curses her and returns the watch she once gave him. She reveals that it was genuine, not a replica, and justifies her decision to marry for Daesan's sake. Dong-ju, incredulous, asks if she loves him, to which she replies that love is not a prerequisite for the union she seeks. As she exits, Dong-ju holds the watch tightly in his hand.
He then seeks solace in a church, where he encounters Sister Agnes, a figure akin to family. Addressing him fondly as Stephanus, she offers him comfort upon learning of his heartbreak. Dong-ju's solace is interrupted by a call from the chairman, summoning him to retrieve more soju for the chairman's safe.
A nostalgic flashback transports us eight years ago, where Gi-hyeon and Dong-ju present Chairman Cha with a flawed Daesan Energy report. Dong-ju, agreeing to partake in an unusual drinking ritual, earns the chairman's trust, leading to a revealing glimpse into the safe filled with liquor. This moment underscores Dong-ju's photographic memory. Returning to the present, Dong-ju retrieves the soju for the chairman's safe, only to discover that the code has mysteriously changed.
Meanwhile, the diligent staff at the Cha residence, at Eun-nam's earnest request, prepares the guest bedroom with meticulous care. Later that evening, Eun-nam chances upon her brother Tae-yun and her mother, realizing with a start that both are privy to her relationship with Dong-ju. The family gathers for dinner, and to Eun-nam's astonishment, the chairman has graciously extended an invitation to Dong-ju as well.
The next morning, Dong-ju awakens with a throbbing hangover, informed by concerned voices that he had indulged heavily during the festive meal. As he stumbles towards his workplace, Dong-ju makes his way to the clandestine meeting room, where, concealed within one of the walls, lies another safe. To his frustration, Dong-ju finds himself unable to unlock it. Chairman Cha enters the scene, revealing his awareness of the truth.
A poignant flashback unfolds, depicting Yeom Jang-seon confiding in Chairman Cha about Eun-nam and Dong-ju's relationship, imploring him to exile Dong-ju from Daesan in exchange for keeping the wedding plans intact. In the present, Chairman Cha confesses his intent to gauge Dong-ju's intentions towards Eun-nam. Dong-ju, baring his soul, recounts the entire tale and volunteers to resign, but his offer is met with Chairman Cha's steadfast refusal. The chairman then personally chauffeurs Dong-ju to a quaint bakery, where among the employees is Ji Yeong-su, a renowned news anchor who mysteriously vanished one day. Also present is Ji Seon-u, Yeong-su's son and Chairman Cha's unrecognized heir, whom the chairman is keen to legitimate.
Returning to the Cha abode, Deok-hui observes the burgeoning closeness between Tae-yun and Dong-ju. A nostalgic flashback reveals Tae-yun aiding Dong-ju in mastering the violin for Eun-nam's sake—a moment that unveiled the truth about their relationship to Tae-yun. Chairman Cha returns home to engage in a discourse with Il-do, who persists in his demand that Dong-ju be removed from their lives.
Equipped with the freshly acquired safe codes, Dong-ju heads to the inner sanctum of the office safe, retrieving a substantial stash of cash and gold. He hands over this treasure trove to Yeom Jang-seon, who instantly recognizes it as the chairman's compensation for sparing Dong-ju's job. Despite Dong-ju's assurance that he won't meddle in Eun-nam's decisions, Yeom remains unconvinced. Just before departing, Yeom's trusted lieutenant brings up a matter concerning Manager Yoo from Daesan, leaving Dong-ju with yet another concern.
Later at the office, Chairman Cha announces that the board views Il-do's appointment as vice chairman as premature, instead appointing Chief Choi Gi-hyeon to the position temporarily. Il-do's disappointment is palpable, and he casts a blameful glance at Dong-ju. Conveying the news to Yeom Jang-seon, Il-do finds him equally faulting Dong-ju.
Acting on Yeom's directions, Dong-ju arrives at Manager Yoo's residence. Finding the door ajar, he steps inside cautiously. To his shock, a knife-wielding assailant leaps at him. In the midst of a fierce struggle, Dong-ju catches a glimpse of Manager Yoo's lifeless body. With a final surge of strength, Dong-ju subdues his attacker. When the assailant's phone rings, Dong-ju answers it, only to hear a voice inquiring if Dong-ju has met his fate. The episode of Buried Hearts concludes on this cliffhanger, leaving viewers eager for more.
