Episode 4 of Buried Hearts premiered on March 1, 2025. In the previous episode, viewers saw Dong-ju survive the fatal attack by Sang-jeon and promise to return the money he skimmed from the fund. Dong-ju (Park Hyung-sik) left for holiday on a yacht and invited Eun-nam (Hong Hwa-heon) but she was kidnapped on her grandfather's orders. Then, Il-do shot Dong-ju on Sang-jeon's orders. Dong-ju was washed up on an island's shore and a local man took him in.
Episode 4 of Buired Hearts opened with Dong-ju waking up from a nightmare where someone was following him in a car. He saw a man come up to his bed with syringes and he tried to fight off but he was rendered unconscious with the injection.
Il-do walked up to the living room as the chairman sneaked some alcohol. Secretary Gong woke up and took the alcohol away. Il-do went back to the bedroom and Secretary Gong recollected seeing him hiding in the office earlier. Ja-ok asked what she was thinking and she just replied that she was thinking about whether to discard the alcohol bottles.
Yeom Sang-jeon grows greedy in Buried Hearts episode 4
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In Buried Hearts episode 4, Il-do and Chairman Cha discussed about Sang-jeon's increasing demands. The chairman was not happy with Sang-jeon's demands, however, Il-do seemed to defend him. The chairman also mentioned that he could remember the passcode for the liquor safe and was unable to reach Dong-ju.
He ordered Il-do to take some cash from his vault to give to Sang-jeon. He brought the passcode chit to Il-do and asked him to click a photo. Il-do was doing his pull-ups at the same spot when he again hallucinated about Dong-ju.
Deok-hui came into the room and addressed her concern about Dong-ju being an obstacle. She asked Il-do to get rid of Dong-ju, and he reassured her that Dong-ju would never be a hindrance again.
Later in Buried Hearts episode 4, Dong-ju once again had a nightmare and someone in the dream called out "Seong-hyeon" and he woke up with a start. Dong-ju got up from the bed and asked for some food. Meanwhile, Guk-hui went to the chairman's office and marked several books to search for safe passcodes.
The next morning, Chairman Cha opened his liquor locker and drank some alcohol with two raw egg yolks. He asked Il-do if he was able to procure the money and Il-do replied that the passcode was incorrect. The chairman said that he would share the new passcode later. He went to his bookshelf to find the passcode but he could not find the chit. The loss of the passcode shocked the chairman and he told Il-do to hold off sharing the money.
How does Won-bae help Dong-ju in Buried Hearts episode 4?
Further in Buried Hearts episode 4, Dong-ju indulged in a meal at Bae Won-bae aka Jang Il-nam's cottage. Won-bae told Dong-ju that he had to stay off the police radar, hence he was unable to take Dong-ju to the hospital earlier. Dong-ju introduced himself as Seong-hyeon.
Won-bae asked Dong-ju how he got shot and Dong-ju replied that he was in a car crash. Won-bae showed the two bullets to Dong-ju and explained how he found Dong-ju. As the two were walking back to the cottage, it began to rain. Dong-ju remembered the night he reached the cottage and how he saved himself from drowning.
The scene in Buried Hearts episode 4 then cut to Sang-jeon's house. Il-do brought some money to Sang-jeon but Sang-jeon dismissed it as the currency was Korean Won and not US Dollars. He expressed his frustration at Il-do's failure to get into the inner circle at Daesan. Sang-jeon ridiculed Il-do but Il-do took it all silently.
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Next, Won-bae showed all the possessions of Dong-ju when he was found on the show. Won-bae warned him against switching the phone on. Eun-nam was in her room when Hui-cheol arrived at her grandfather's request. She was threatened to return to her in-laws' house if she wanted to keep the shares.
Shortly after in Buried Hearts episode 4, Eun-nam's phone rang in her room and Hui-cheol answered it. Hui-cheol and Dong-ju (Seong-hyeon) spoke a little but the phone went dead mid-conversation.
Eun-nam met with the chairman to talk about the threat. The chairman told her that her marriage was a deal between him and her in order to have the shares for her. She would have to continue being Sang-jeon's niece-in-law if she wanted to keep the shares.
Hui-cheol went out of Eun-nam's room, looking for Eun-nam's mother. Secretary Gong was storing the alcohol bottles away and answered she was in the main living room. He asked her to bring him some ice water. Hui-cheol handed the phone to Eun-nam's mother and told him that Dong-ju introduced himself as Seong-hyeon in Buried Hearts episode 4.
Buried Hearts episode 4: What is Secretary Gong hiding?
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Secretary Gong overheard Hui-cheol narrate his conversation with Dong-ju and she was stunned. Hui-cheol was determined to take Eun-nam with him. The chairman announced a feast in celebration of Hui-cheol's birthday two months later. Eun-nam did not get her phone back.
Later in Buried Hearts episode 4, Il-do reached his office to find out that the Secretary's office staff was talking to the Coast Guard regarding Dong-ju's disappearance. Won-bae and Dong-ju logged into a computer at an internet cafe to search for news on Dong-ju's case. There were no results but they could find a report about a missing one-year-old boy.
Chairman Cha, on the other hand, tried to remember the password to his vault. Il-do informed him that Dong-ju's yacht was found but Dong-ju was missing. The chairman asked Il-do to quickly find Dong-ju as he was facing difficulty at work without Dong-ju.
Won-bae was curious about Dong-ju's identity. He received a phone call from a person named Chang-gyu who had fixed Dong-ju's phone. Chang-gyu told Won-bae to discard the phone if it was damaged again.
Later that night in Buried Hearts episode 4, Deok-hui handed Eun-nam's phone to Il-do and asked him to call Dong-ju and settle the matter once and for all. She narrated the earlier incident with Hui-cheol and Il-do was surprised.
Won-bae and Dong-ju took a bus back to the cottage. Dong-ju received a phone call from Il-do who was, in turn, surprised to find that Dong-ju was alive. He made a mental promise to kill Dong-ju and hung up without a word.
Won-bae launched into theorizing about the unknown caller and Dong-ju's past. The phone went dead immediately. Il-do informed the news about Dong-ju to Sang-jeon. Sang-jeon began to prepare for the next plan to bring Dong-ju and get the passcodes. He would kill Dong-ju once he had the passcodes as revealed in Buried Hearts episode 4.
Buried Hearts episode 4: Does Il-do find Dongju?
Further in Buried Hearts episode 4, Il-do and Gu-ho left for Dong-ju's location in a helicopter. Dong-ju and Won-bae took a boat out to the sea. The little boy from the previous episode watched them leave from the docks. Il-do reached Dong-ju's yacht whereas Won-bae and Dong-ju scoured the nearby area for possible car crash sites.
Il-do searched Dong-ju's yacht and recollected the past events. Won-bae and Dong-ju's boat crossed the yacht but Il-do did not notice them. Won-bae told Dong-ju that it was impossible for Dong-ju to reach the shore if his car had fallen off the cliff on the other side.
Sang-jeon was also speaking to a mysterious man earlier about some package. Il-do informed Sang-jeon about Dong-ju's absence from the yacht. Meanwhile, Gu-ho began searching for Dong-ju in Buried Hearts episode 4.
Gu-ho found Chang-gyu's shop, whereas Il-do finally saw Dong-ju on the boat with Won-bae. Il-do fell into the sea as he tried to get onto the smaller boat. Dong-ju jumped in to save him and admitted him to a hospital.
Dong-ju contracted fever and saw a nightmare. Meanwhile, Il-do recollected Dong-ju saving him from drowning. Gu-ho kept guard for Il-do and he was ordered by Sang-jeon to continue looking for Dong-ju.
Later in Buried Hearts episode 4, the same mysterious man from earlier had a torture room prepared for himself.
Buried Hearts episode 4: Has Dong-ju really lost his memory?
The little boy, whom viewers saw in Buried Hearts episode 3, spoke to Gu-ho and the boy smiled in recognition of Dong-ju's photo. Gu-ho finally located Won-bae's cottage but the duo had left by then. Gu-ho called Sang-jeon with an update.
In a short flashback, it was revealed that Won-bae changed his appearance and helped Dong-ju escape. Il-do spoke to Eun-nam to ask if Dong-ju had contacted her. Hui-cheol overheard the conversation and said that he hoped Dong-ju would disappear or drop dead so that Eun-nam would pay attention to him.
Eun-nam fixed his tie and said that she missed the man that Dong-ju was. Hui-cheol tried to kiss her but she resisted. She reminded him to meet later to pick up his suit. Later, on her way to pick up the suit, she stopped at a signal but missed Dong-ju who was crossing the street in Buried Hearts episode 4.
She waited for Hui-cheol at the boutique and co-incidentally Dong-ju was present there making an enquiry about his suit. Hui-cheol looked at the suits picked for him by his mother-in-law. As the couple was leaving, they spotted Dong-ju. Eun-nam approached Dong-ju but he acted like he did not remember her.
Episode 5 of Buried Hearts will air on Friday, March 7, 2025.