One of the bodies entrusted to Seo Se-hyun, a promising soup autopsy. The thread sutured with the smell of rocks in the body reminds me of her past. Jung Hyun, the head of the strong team, is in charge of the investigation.

In Yongcheon, a carcass with a thread is found, and the identity of the body is found to be the missing team of Se-hyun. Se-hyun, who discovered the same technique and clues in the second body, feels that the bacteria are back.