The episode begins with a flashback, revealing a call from Do Eun-hyuk to Seol-ah, informing her that Seung-jae was in an accident. Seol-ah goes to the dock and identifies his body, but her lack of emotion raises eyebrows.
At present, Woo-seok questions Seol-ah about her fiancé's death. A man named Eun-hyuk, who seems close to Seol-ah, interrupts them and Woo-seok takes his leave.
A flashback shows Seung-jae and Eun-hyuk drinking together. Seung-jae had just opened a restaurant, the logo of which was the siren, a mythological creature. While talking, Seung-jae admits to Eun-hyuk that he sometimes feels like he doesn't know Seol-ah at all. He also mentions that he's taken out insurance in her name.
At present, Eun-hyuk and Seol-ah go to Sook-ji's bar and have a drink. A young girl sees Eun-hyuk with Seol-ah and tries to call him, but he cuts the call.
Meanwhile, Woo-seok sets up a murder investigation board at home. He visits Yun-ji's mother and informs her about the insurance payout. While he's there, Seol-ah comes by to drop off Yun-ji's things. Woo-seok helps them carry the box up to Yun-ji's room, where each of them does a little snooping.
Seol-ah finds that Yun-ji had kept track of her schedule on a calendar, while Woo-seok finds Yoon Seung-jae's business card! When they go downstairs, Yun-ji's mother mentions that Yun-ji was dating someone and was upset because of him. Before parting ways, Woo-seok and Seol-ah exchange a few terse words once again.
Meanwhile, Seong-il goes through Yun-ji's phone records and finds Seung-jae's name quite a few times. The next day, Woo-seok engineers a scheme to catch a group of people involved in an insurance fraud ring. He hands them over to a policeman named Detective Kim, who, in turn, gives him information on Seung-jae's death. Kim tells him that Seung-jae was alone on the boat and must have fallen into the propellers. However, he says that Seol-ah's lack of reaction was a bit odd.
A flashback shows Seung-jae and Seol-ah out on the yacht, drinking. He tells her not to worry since he's cancelled the insurance policy. At present, Seol-ah meets Chairwoman Kim and their conversation makes it clear that Kim knew Seol-ah's family when she was a kid. She says she's cooked Seol-ah's favourite seafood and they eat together, but Seol-ah later throws it all up.
Woo-seok's probing leads him to Seung-jae's restaurant, where he discovers that Kim Yun-ji had been a frequent visitor. A staff member informs him that Yun-ji had paid a visit to Seung-jae the day before his tragic death. Seong-il also arrives at the restaurant, and the two men exchange tense words before parting ways. Seong-il clearly believes that Woo-seok's sister's death was just an unfortunate accident.
Woo-seok meets Seol-ah at Sook-ji's bar and asks if she knew about Yun-ji's meeting with Seung-jae. He reveals that Yun-ji had tipped him off about a murder and directly confronts Seol-ah about whether she was responsible for both deaths. She remains unperturbed. Later, Woo-seok tells Joo-young that he has studied Seol-ah's microexpressions and believes she didn't know about Yun-ji and Seung-jae. However, he decides to investigate any suspicious incidents from Seol-ah's past to see if she's tried anything like this before.
The next day, Seol-ah arrives at work to find herself surrounded by whispers about how she mistreated Yun-ji before her death. At this point, we learn that Eun-hyuk is a photographer and Seol-ah's best friend. The young woman spying on him was his sister, Eun-hye, who suspects Seol-ah of having killed Yun-ji. Eun-hyuk tells her that Seol-ah is the one who granted her an internship and scholarships because she considers them family.
At the hospital, Woo-seok visits Chae-rin, who finally decides to tell the truth about her mother. Woo-seok then receives a call about another insurance policy connected to Seol-ah. This one was taken out by a psychiatrist named Choi Young-ho, who listed Seol-ah as the beneficiary for 500 million won. The doctor committed suicide, but the insurance policy was cancelled just before he passed away.
Despite his boss' orders to let the matter go to the police, Woo-seok goes to Choi Young-ho's hospital and makes some inquiries. He learns that Seol-ah was a patient there and a nurse named Mi-yeon tells him - after a bribe - that Seol-ah had just broken up with a boyfriend and came to the clinic for depression. There, she met and fell for Young-ho, who dumped his own girlfriend for Seol-ah. Apparently, Seol-ah's first boyfriend died in a terror attack in the Middle East.
Meanwhile, Seol-ah shreds the papers from Yun-ji's calendar with her name on it. Suddenly, Eun-hyuk arrives and asks Seol-ah if she received an insurance payout. Seol-ah is upset that he, of all people, is not on her side and storms off. On the drive home, she sees an advertisement for Woo-seok's insurance agency and smirks.
Woo-seok delves into Seol-ah's first boyfriend and learns that he was a Korean NGO worker who died in Syria during a terror attack. The next morning, a painting arrives at the auction house for Seol-ah. It's called "An Orphan from Syria" and depicts a Syrian child sitting amidst the wreckage of a street. The painting seems to affect Seol-ah. Some time later, Seol-ah is watching a slideshow of paintings when Woo-seok shows up again. He narrates all he's found, claiming that whoever loves Seol-ah ends up dying. Seol-ah challenges Woo-seok by asking if he knows who will fall for her and die next.
