In the second episode of "In Your Radiant Season," Seonu Chan's story picks up where it left off—with him being hit by the explosion at the Boston university. As he awakens in the hospital, he returns to South Korea for medical treatment. However, his memories from the year prior to the accident are gone, and though he can clearly see Ha-ran's face, he can't remember who she is. One day, while out on the street, he spots her and follows her. He's about to approach her when fireworks explode, triggering his memory.
A flashback shows Ha-ran talking on the phone with another student, Kang Hyeok-chan. The call is on speakerphone, allowing Chan to hear her sing a melody to Hyeok-chan. One day, Hyeok-chan asks Chan to respond to Ha-ran on his behalf and tell him he's in the lab. But Chan sees that Ha-ran is feeling down and starts talking to her. When Hyeok-chan goes on a holiday, he switches laptops with Chan by mistake. He simply tells Chan to ignore Ha-ran's messages, but that's clearly not what happened.
Switching back to the post-accident timeline, the fireworks force Chan to remember everything and he walks away. We then jump to the present, where Ha-ran confronts Seonu Chan about his "stalkerish" behavior. Chan explains that he had looked up Nana Atelier's employees beforehand, which is how he knew her name at the art gallery. This seems to pacify her and she walks away. But a person dressed in black walks behind Ha-ran and Chan spots him. He raises the alarm and both of them chase the person, who throws a bottle at Ha-ran. Chan stands in the way and it hits his jacket.
The person in black is revealed to be a woman! Also involved in the chase are Ha-young, who was keeping an eye on Ha-ran, and Yeon Tae-suk (the COO at the atelier), who bumped into Ha-young. They all head to the police station, where it is revealed that the woman used to work with Ha-ran many years ago. She resented Ha-ran being the center of attention and quit her job out of jealousy. Ha-ran recognizes her and decides not to press charges.
When the police disclose that Chan might require medical attention, Ha-ran swiftly goes after him, leaving her contact card with him, determined to pay for any injuries and the destruction of his jacket. Back at home, Ha-young ingeniously convinces Na-na that Ha-ran is engaging with a potential boyfriend, thereby ending Na-na's incessant nagging about dating. She then suggests that Ha-ran give Chan some new clothes as a token of gratitude.
A flashback reveals that Ha-ran once put all their family's shoes in the bathtub, preventing them from leaving the house. She pleaded with them to stay put. Presently, Ha-young ponders this and her sister's concern when she realized Ha-young wanted to capture the stalker.
Currently, Ha-ran drops off new clothes at Chan's hotel. As it's raining, he offers her an umbrella, but it's broken. Just then, an old acquaintance approaches Ha-ran and tries to engage her in conversation. Ha-ran clearly doesn't want to answer questions about her absence and panics, following Chan to his room to escape. They awkwardly wait for Ben to return to get another umbrella.
Meanwhile, Mr Park, the owner of the café Ha-ran frequents, falls ill and ends up in the hospital. Ha-ran finds his dog, Genius, alone at the café and brings him home while Mr Park recovers. Later, Mr Park visits Ha-ran's house to retrieve Genius. He meets Na-na, who recognizes him as Park Man-jae from her hometown in Chuncheon. They catch up and talk about Ha-ran as well. He recounts how he found Ha-ran crying in the rain outside his café seven years ago.
Elsewhere, Ha-ran sees that the café's lights are on and goes inside. She's surprised to see Chan there as he's decided to live with the old man for the three months he's in South Korea. He says he's been a regular at the café since he arrived in Korea. Mr Park returns to the café and greets both of them.
The next day at work, Na-na notices the name Seonu Chan written inside Ha-ran's folder (she had done this when she thought he was her stalker). So Na-na turns a work meeting into a dinner and then leaves them alone. Ha-ran gets a text from Na-na that makes her realize what's happened. Nevertheless, she asks Chan not to tell Na-na the truth about the misunderstanding.
When one of the restaurant's speakers malfunctions, Chan's injury acts up and makes him disoriented. He rushes outside to calm down, and she follows. In the chaos, her engraved pen falls and gets lost. He tells her about his injury, and she offers her scarf to cover the stain on his shirt. She says she'll tell her grandmother about the misunderstanding since she doesn't want to feel indebted. He wonders about how she keeps drawing a line between them.
Ha-ran shows up at work with a cold the next day. She panics when she realizes she's lost her pen and rushes back to the restaurant but they don't have it. A flashback shows Hyeok-chan asking Chan to get a gift for Ha-ran since he's going downtown anyway. Presently, Chan offers to search for the pen with Ha-ran after the restaurant closes but she insists it's a personal matter and tells him to leave.
When he's back home, we see a small cutting of a plant sitting in a glass of water. It was wilting, and Chan decided to try and revive it. Mr Park points out that it has grown roots and it's time to put it in a pot, which makes Chan think about Ha-ran's situation. Mr Park also notices his "memento mori" tattoo and asks if he's truly living without any regrets. Chan ponders this and then runs back out of the house.
Ha-ran can't find the pen at the restaurant and is about to leave when Chan meets her again. He tells her he wants them to meddle in each other's affairs, feel indebted, and get to know each other over the next three months.
A flashback shows that Chan was going to commit suicide when Ha-ran's messages on his/Hyeok-chan's laptop distracted him and made him stop.
