The Scarecrow Episode 4 begins with Young-woo and Tae-joo engaging in an honest conversation about their respective pasts, opting to share personal experiences to gain insight into one another.
The story then cuts back to 1988. Tae-joo wakes up in the hospital and goes to the autopsy room where a disturbing new detail comes to light. This murderer was not the same as the last. He cut a message into Min-ji’s chest. “The killer also stuffed her body with sand and toffies, the doctor says. Tae-joo recognizes the candy. It’s the same candy Min-ji gave him the last time they met. Disturbed, he begs Si-young to let him stay on the case, determined to find the murderer. Si-young thinks about the request and says they might work together again.
We see a flashback of their complex history. Back in high school, Si-young came up to Tae-joo and asked to be friends. Si-young offered to pay Tae-joo to tutor and Tae-joo initially refused but finally agreed. When Si-young’s mother would leave snacks for them during their study sessions, Tae-joo would secretly save some for Sun-young. Later, Si-young asks Tae-joo to the same college but his mother makes him earn the money himself. The next day, however, Si-young abruptly stopped him in his tracks, mocking his mom’s job and cutting off all contact.
Chief Park Eun-kyu discusses the case with his team in 1988. Man-chun protests Tae-joo’s dismissal, saying that Kyung-ho lied about the attack. Not long after, Superintendent Cha Jun-young orders Tae-joo reinstated. Tae-joo is surprised to hear the news.
Elsewhere, Si-young thanks the superintendent for the favor and offers to help with his father’s political ambitions in return. His marriage to a politician’s daughter, Hee-jin, as a way of entering politics, is criticized.
At the station, Dae-ho confronts Tae-joo about dropping the case. Tae-joo takes him out for dinner, explaining that he left to keep a promise. He remembers Min-ji’s last words and vows to find her killer, no matter what.
Later, Tae-joo sees Ji-won release a blurry photo of the suspect and asks whether it will elicit the killer’s response. It does. The killer sees the picture and goes nuts. Tae-joo goes to the newsroom to see Ji-won, who explains how she got the photo while being chased. Tae-joo looks at the handkerchief over the killer’s face, trying to figure out what it is.
Elsewhere, Sun-young takes a break from school to recover. Meanwhile, Si-young has a meal with Hee-jin. They run into her friend, but the mood turns tense as Hee-jin gives a cold response. Si-young is disturbed by the reason for the woman’s behavior that she later explains is her background.
Si-young almost hits Sun-young while driving, but manages to stop in time. He apologizes and notices she is hungry so he buys her some snacks. He offers her a ride home, but she says no.
As Sun-young walks away, Kyung-ho follows and attempts to attack her. Gi-beom intervenes and stops him, but the situation escalates into violence. Around the same time, Tae-joo examines Min-ji’s belongings and finds sketches of the suspect. Ki-hwan reveals that Gi-beom had followed Min-ji the night she died. Soon after, police arrive to arrest Gi-beom for assaulting Kyung-ho.
Tae-joo informs his team that Gi-beom is now on the run. He later meets Si-young and asks him to convince Kyung-ho to drop the charges, hoping to prevent Gi-beom from fleeing. Si-young agrees but suggests Gi-beom could also be a suspect.
Un-hui and Dae-ho inform Ji-won and Sun-young about the situation. Shocked, Ji-won comforts Sun-young and takes her home. Instead, Sun-young goes to a hidden location where she is sheltering Gi-beom. A flashback reveals she stopped him from killing Kyung-ho and convinced him not to turn himself in. She now asks him to run away with her.
Meanwhile, Si-young pressures Kyung-ho in the hospital to drop the charges, threatening his reputation. Tae-joo overhears the conversation and later learns that Si-young had exposed the truth about his mother in the past, leading to years of bullying.
Ji-won makes a key discovery—Sun-young’s handkerchief matches the one used by the killer. That night, Tae-joo confronts Si-young about targeting his sister. Si-young brushes it off and claims he wants a fresh start, but Tae-joo refuses to forgive him. Ji-won interrupts with her findings, suggesting Gi-beom may be the killer. Tae-joo immediately orders a search for both Gi-beom and Sun-young.
At the same time, Gi-beom locks Sun-young in a room and escapes alone. Before she can get out, the real killer reaches her. Si-young arrives at the scene and finds her unconscious. As he searches for the attacker, Tae-joo and Ji-won arrive. They grow suspicious after finding Sun-young’s belongings in Si-young’s car.
A gunshot is heard. Tae-joo rushes into the field and finds Si-young carrying Sun-young. Si-young claims the killer escaped and that he was shot during the struggle. As help is called, Si-young reflects on their past.
A flashback reveals the truth—Si-young overheard Tae-joo’s mother refusing to support his education and intentionally pushed Tae-joo away to stop him from following the same path. Later, he discovered his father’s connection to Tae-joo’s mother.
Back in the present, Si-young reveals to Tae-joo that they are half-brothers before losing consciousness. Meanwhile, Gi-beom is arrested, but the real killer remains at large. Tae-joo rushes Si-young into surgery.
In 2019, Young-woo asks if Tae-joo stayed in touch with Si-young and whether working with him changed his life. Tae-joo responds with a heavy truth—he lost everything because of that partnership.
Episode Review
This episode delivers a major emotional and narrative punch. The revelation that Tae-joo and Si-young are half-brothers adds a powerful new layer to their already complicated relationship. Si-young’s actions in the past now take on a different meaning—he tried to push Tae-joo away, but his methods caused lasting damage.
The family drama is compelling, but the central mystery remains just as gripping. Gi-beom’s situation feels like a misdirection, and there are still strong reasons to question his guilt. The possibility that someone closer to the investigation is involved raises the stakes even further.
There is also an intriguing suggestion that the killer may be dealing with memory issues, which could explain certain inconsistencies. As the story moves forward, the tension continues to build, leaving several key questions unanswered heading into the next episode.
