In the second episode of "Had I Not Seen the Sun," we're whisked back to 2007 as a concerned teacher and school counselor interrogate Jen-yao about the bruises adorning his face. Their anxiety is palpable, wondering if he's been the victim of bullying, both within and outside the school's walls.
Flashbacks reveal that Jen-yao sustained his injuries due to harassment by his father's creditors, who were also beating him at home. Rather than unburden himself, he tells a lie, claiming he fell off a motorcycle. Meanwhile, Hsiao-tung, part of the school's dance team with a penchant for her mother's packed chicken leg, abandons her friends to practice ballet on the school roof.
As Jen-yao exits the office, he stumbles upon Hsiao-tung's choreography and is captivated. They both conspire to sneak around the school to buy a chicken leg bento, returning to the rooftop for a meal that evokes a sense of camaraderie until the bell rings. Hsiao-tung departs, promising to meet again at noon the next day.
That night, Jen-yao collects his wages from his part-time job at a dish-cleaning gig. On his way home, he runs into the debt collectors once again, who press him about his father's whereabouts. Jen-yao maintains a lie that his father is out of town, but their knowledge of his injuries exposes his deception. The debtor takes all his earnings to cover his father's interest for the week, threatening to come after Jen-yao if he doesn't lead them to his father.
Jen-yao hurries home and steers his mother out of the house, having made a pact to shield her from the debtors' wrath. Realizing his mother's refusal to leave without him and her steadfast determination to help her husband, Jen-yao watches from the window as she comforts his father and they hold hands as the debtors depart. The weight of his anger and sadness overwhelms him, propelling him towards Hsiao-tung's shop. However, upon seeing her beaming with joy while serving customers with her parents, he hesitates and chooses not to interrupt her moment of bliss.
The following day at school, Jen-yao's absence from the rooftop is noted. During ballet practice, Hsiao-tung is chosen for the lead role in the upcoming school dance. Her friends shower her with congratulations, but one figure seems displeased. As Hsiao-tung chats merrily with her companions, Jen-yao passes by the dance room. Hsiao-tung spots him and waves, but he ignores her, strolling away as if nothing had happened.
The scene abruptly shifts to a rainy night, as Chan En-ya runs for her life through the woods. Jen-yao follows closely, wielding a crowbar. The girl's pleas for mercy fall on deaf ears, and her fate is sealed when Jen-yao brings the crowbar down on her head.
Fast-forward to 2023, and Pin-yu fails to appear at work. Ta-wei attempts to reach her by phone, but when she does eventually show up, she appears in a daze before a train platform. A tap on her shoulder snaps her back to reality. Later, Yun-chen picks her up after receiving a call from the police.
Pin-yu has no recollection of how she found herself at the train station. The building manager informs Yun-chen that he had seen her leave in a daze. Her last memory is of the uniformed girl (Hsiao-tung), and she suspects that she was possessed by her.
Upon returning to her apartment, they request to review the CCTV footage. Pin-yu is seen crying in the elevator, but she has no recollection of entering it. Inside the house, her research materials on Jen-yao's case are scattered across the floor. She also finds several searches about him on her computer, which she does not remember conducting.
Pin-yu, still unsettled by the notion of possession, theorizes that she may be one of Jen-yao's unlucky victims. Just as her thoughts spiral out of control, a call from Ta-wei reminds her of the upcoming interview, urging her to hustle out the door.
The day's interviewee is Officer Lao, who was intimately involved in Jen-yao's gruesome serial killing case. Lao explains that Jen-yao's first murder was a sloppy affair, as if it were an impulsive act. However, his subsequent killings became more meticulous, a sign of his growing cold-bloodedness. He meticulously cleaned up the crime scenes, leaving no trace for the police to follow and disposed of the bodies with care. In fact, he became so heartless that he even indulged in a bowl of noodles after dispatching Lin Meng-hung.
Ta-wei inquires about the items Jen-yao burned after killing Chang En-ya in the woods, believing them to be incriminating evidence. However, Lao reveals that he only burned photos taken from En-ya's apartment and her ballet dresses. A visual of Jen-yao burning pictures of the ballet group next to En-ya's body is depicted.
At the end of the interview, Ta-wei asks Lao what he thought was special about Jen-yao. Lao responds that during his confession, Jen-yao was honest about the people he killed, the timelines, the methods of their demise, and their final resting places. However, he never divulged his motive, as if he were guarding a significant secret.
That night, Pin-yu attempts to reason with the unseen presence in her room, imploring it not to possess her without warning or appear out of nowhere, as it is terrifying. Her doorbell rings, and she cautiously opens it, remembering the neighbours' mention of ringing doorbells. Fortunately, Yun-chen is there to keep her company, as Pin-yu worries she might sleepwalk again.
The next morning, Yun-chen leaves early. As Pin-yu prepares to leave for work, she runs into one of the neighbours and decides to inquire more about the girl who previously occupied her room. She learns that it was Chan En-ya, and she heads back to the room to investigate further.
Pin-yu calls Yun-chen and shares her discovery, but after looking up En-ya's pictures online, she doesn't think she's the girl in uniform. Yun-chen cuts her off, saying she has something to do. As Yun-chen stares angrily across at Jen-yao, a flashback takes us back to 2007 when Jen-yao, Hsiao-tung, and Yun-chen attended the same high school.
