Episode 1 of "Buried Hearts" kicks off with an eerie sight: a dilapidated raft carrying the lifeless body of an unknown man, discovered by a fisherman casting his net for octopus. Greedily, the fisherman pockets the deceased's watch, unaware of its significance.
The narrative then pivots to a court hearing, where Huh Il-do represents Daesan Group, entangled in a contentious scandal regarding discrepancies in an energy project under Daesan Energy. Present at the hearing is Seo Dong-ju, whose wrist sports the very same watch pilfered earlier. Dong-ju serves as a conduit, relaying the hearing's proceedings to an elderly man confined to his home, who curtly instructs Dong-ju to terminate the transmission.
A poignant flashback unveils Dong-ju in a clandestine meeting with Assemblyman Nam Sang-cheol. Dong-ju presents two boxes brimming with US dollars, courtesy of Chairman Cha Gang-cheon, in exchange for adjourning the hearing. However, the assemblyman's nephew, ever vigilant, detects a hidden camera on Dong-ju and promptly confiscates it.
Undeterred, Dong-ju persuades Sang-cheol to converse in private, revealing a second, cleverly concealed camera attached to the assemblyman's feline pet. Confronted with such ingenuity, Sang-cheol caves in and inks a paper affirming his deal with Chairman Cha. In the present, Sang-cheol orchestrates a commotion during the assembly, successfully securing its adjournment. The elderly man on the other end of Dong-ju's call expresses satisfaction with his duplicity.
Huh Il-do, too, lauds Dong-ju's prowess before heading towards an opulent mansion, where he greets his wife, Deok-hui, the chairman's beloved daughter. Meanwhile, Dong-ju awaits Chairman Cha in a grand office, his curiosity piqued. He cracks open a safe, extracting two bottles of soju, setting the stage for further intrigue.
Il-do storms into the room, his resentment palpable as the conversation unfolds, revealing his deep-seated bitterness over Dong-ju's favored position in Chairman Cha's trust, while he himself remains on the fringes. A poignant flashback transports us to the moment when news of the energy project hearing broke, Chairman Cha rushing to consult Dong-ju before even considering Il-do.
In the present, Chairman Cha, Il-do, and Dong-ju share a drink, the ambiance tense. Suddenly, Deok-hui arrives, diplomatically excusing Dong-ju to facilitate a family discussion. Il-do drops a bombshell, revealing that Yang Jang-seon has extended an offer directly, an anomaly as he typically communicates through Dong-ju. Confusion deepens as Dong-ju is promptly instructed to end his workday early.
Later, at the office, Yeo Eun-nam, an employee from Daesan Energy, is introduced. Dong-ju is summoned to see the chairman but cannot help but cast a lingering glance at Eun-nam. Stepping inside, he is astounded to find the enigmatic old man from earlier scenes – Yeom Jang-seon – awaiting him. Chairman Cha and Il-do are also present. The quartet retreats to a hidden chamber behind a discreet wall, where they delve into the intricacies of merging Daesan Chemical with Yuseong Chemical. With a swift phone call, Yeom Jang-seon seals the deal.
Returning home, Dong-ju encounters Yeo Eun-nam unexpectedly. Over dinner, their conversation veers towards Dong-ju's watch, which Eun-nam reveals to be a fake, not the genuine article. Just then, Dong-ju receives a call from his senior, Chief Gi-hyeon, informing him of Chairman Cha's granddaughter's impending return from the US for her wedding. Dong-ju readily agrees to assist in the arrangements. Gi-hyeon, with a hint of nostalgia, inquiries if Dong-ju harbors any regrets about not pursuing the granddaughter. Later, Eun-nam too reminds Dong-ju of his intended journey to the US to court Cha's granddaughter, a plan sidetracked by his unexpected encounter and subsequent infatuation with Eun-nam.
The following day, Dong-ju discovers Cha Guk-hui, the other daughter of Chairman Cha, awaiting him in his office. She urges him to align himself with her if he wishes to secure his future at Daesan, but Dong-ju remains steadfastly loyal to the chairman. Soon after, Dong-ju meets with Chairman Cha, who ponders the notion of elevating Il-do to the position of vice chairman, a prospect that does not resonate well with Dong-ju. He is tasked with gathering feedback from the company's board members regarding this proposal.
Dong-ju joins Il-do on his helicopter and is compelled to disclose the purpose of his mission. After a brief journey spanning several days, Dong-ju returns to a cordial reception by Eun-nam right at the office premises. However, he is promptly whisked away to attend to his duties, causing Eun-nam's smile to diminish.
Gi-hyeol is displeased with Il-do's prospective vice chairmanship. Dong-ju proposes a mutually beneficial arrangement: Gi-hyeol will recommend Dong-ju for the head position in the chemical sector, while Dong-ju will, in turn, advocate for Gi-hyeol's presidency at Daesan Energy.
In the intimacy of their home, Dong-ju and Eun-nam bask in a bathtub adorned with candles and rose petals. Eun-nam drops cryptic hints about a possible breakup, prompting Dong-ju to joke that if that were to occur, he would seek revenge by arriving at an event with another woman on his arm. Later, Eun-nam's frustration escalates during a phone conversation. She emerges to find Dong-ju collapsed on the floor after ingesting a cinnamon-laden part of a sandwich, prompting her to rush him to the hospital.
A flashback unfolds, revealing Dong-ju and Gi-hyeol discussing a trip to New York for Dong-ju to present persimmons to Chairman Cha's daughter, Jennifer Huh. Dong-ju catches sight of Eun-nam nearby, lost in her music, and finds himself captivated by her presence. She approaches him later, scolding him for reporting her mistake in a report to the chairman, which led to her being reprimanded by the chairman. Instinctively, Dong-ju invites her to join him for dinner and subsequently informs Choi Gi-hyeol that he will not proceed with the New York trip.
In the present, Dong-ju awakens in the hospital, where it is revealed that the sandwich's bread contained cinnamon, an allergen for Dong-ju. Eun-nam is distraught, expressing her disappointment that she had intended to make the evening special. Later, they return home and share an intimate moment.
The next morning, Dong-ju is awakened by a call from Secretary Gong, informing him that Chairman Cha desires his presence at Jennifer's wedding. Dong-ju dresses for the occasion but finds Eun-nam missing. He glances at a box containing diamond engagement rings and sends Eun-nam a text, suggesting they have dinner together.
He, accompanied by Chairman Cha, arrives at the ornate wedding venue, where Dong-ju's path soon crosses with Yeom Hui-cheol. Hui-cheol, the nephew of Yeom Jang-seon and Dong-ju's former high school acquaintance, harbors mutual disdain towards each other. Dong-ju's astonishment knows no bounds when he discovers that Hui-cheol is the groom of the hour.
As Buried Hearts Episode 1 draws to a close, the wedding ceremony commences, and to Dong-ju's utter amazement, Jennifer materializes as Yeo Eun-nam. His heart shatters into a million pieces as he beholds her gracefully descending the aisle. Before he can so much as utter a word or make a move, a contingent of security guards swiftly restrains him, leaving him helplessly witnessing the unfolding scene.
