The discovery of skeletal remains and a student card with Lee Ha-neul's name at Sopyung Lake marks a significant shift in the investigation. Kang-san is heartbroken, fearing the loss of his brother. Meanwhile, Hye-kyung becomes suspicious of Tae-man's attention towards the boy living with Dong-ju. Acting as if she is unfamiliar with the boy, Hye-kyung accepts Kang-san's picture from Tae-man but immediately visits Dong-ju's house, bringing a mysterious gift.