In the third episode of "Siren's Kiss," the confrontation between Woo-seok and Seol-ah intensifies as he brings up her three deceased boyfriends and wonders if the canceled insurance policies could be a cover-up for something more sinister. Seol-ah remains silent, providing no explanation.
Later, Woo-seok notices that Hyun-su's fruit shop has closed down. A neighbor informs him that the owner took compensation from the builders who want to redevelop the area, much to the locals' dismay.
The next day at work, a video of the conversation between Yun-ji and Seol-ah (the one in the dressing room) surfaces online. Someone was secretly recording them. Woo-seok and Young-soo see this and are shocked. Seol-ah meets with Chairwoman Kim and the managing director, Song Jae-uk, about the matter. The latter is blaming Seol-ah for the commotion when she pulls out screenshots from Yun-ji's computer that show Yun-ji sent the director compromising photographs and he promised her a promotion.
Chairwoman Kim berates both of them for adding fuel to the fire. She orders them to create a distraction by bringing in a famous painting by an artist named Emil Stiller to their auction. Whoever succeeds in doing so will be first in line as her successor. After they leave her office, Chairwoman Kim opens a secret vault. Inside, all the walls are covered in valuable paintings, including one by Artist Han, who seems to be Seol-ah's father. Kim tells him that his daughter isn't like him.
At the police station, the detectives find CCTV footage that shows both Yun-ji and Seol-ah going up to the 12th floor one after the other. Seong-il tells Joo-young to find the anonymous caller who left a tip against Seol-ah. Joo-young ends up joining hands with Woo-seok. They go to the location of the public call box, and Woo-seok sweet-talks a store owner into giving up the dash cam footage of her truck parked outside. Joo-young goes through it and sees a young woman in a hooded jacket leaving the message.
Meanwhile, Seol-ah delves into research on the Stiller painting at home, her mind racing with questions. Suddenly, there's a knock at the door, and a bottle of wine is left outside. It's one of Yoon Seung-jae's bottles! The next morning, her security guard informs her of the delivery man's company name, and Seol-ah traces the order back to Eun-hyuk's house. Confronting her friend, Eun-hyuk reveals that Seung-jae asked him to send it. Just then, Eun-hye shows up and confesses that she sent the bottle because Eun-hyuk was hesitant to do so. A flashback reveals that Seung-jae gave Eun-hyuk the bottle and asked him to give it to Seol-ah in case something happened to him.
The next morning, after striking a deal with his company's general insurance team, Woo-seok arrives at the auction house as the company's fine art insurance account manager. Seol-ah takes this in stride and gives him a tour of the building, including a storage vault housing priceless artworks. He questions her again but she remains cool, warning him not to show up unannounced again.
After she leaves, Woo-seok searches for Yun-ji's car and finds it in the office parking lot. He breaks in and searches through it, finding a key card for a place named Luen Palace.
Seol-ah visits a woman who runs a gallery and whose husband is the vice president of Christie's auction house in Hong Kong, where the Stiller was bought by a Korean man. The woman asks Seol-ah to feature the painting of a rich CEO's daughter (hence boosting her own sales) and, in return, tells her that the man who bought the Stiller went by the name James Paek. Seol-ah begins to wonder if James could be Paek Jun-beom, whom we saw in Episode 1.
She invites him to the auction house for a private viewing and shows him the painting of the Syrian child. The conversation between them reveals that he is the one who sent it to her but it doesn't quite explain why it was anonymous. Jun-beom takes her out for dinner, where she brings up the Stiller. Turns out, he does have the piece but is disappointed that she's more interested in that than in him. He's not keen on selling it either.
As for Luen Palace, Woo-seok and Young-soo find over 70 studio apartments with the same name in the city. To help narrow things down, Woo-seok visits the owner of a delivery service whom he had sent to jail for an insurance scam. He's in the middle of one now as well and Woo-seok gives him a chance to avoid prison - he has his deliverymen spread out through the city and find the apartment complex that matches Yun-ji's key card.
At the police station, the detectives find the anonymous caller who is none other than Do Eun-hye. She tells them that she saw Seol-ah kill Yun-ji. At the same time, we see Woo-seok finding the correct Luen Palace apartment. Inside, there's not much except for a toy model of a house sitting on a coffee table. He goes to the balcony and is surprised to see that this apartment is right across the street from Seol-ah's apartment.
