Yo Han tells Si Young to keep his condition a secret. Si Young worries about Yo Han after she knew about his disease. Yo Han calls in sick, and Si Young goes to his house because she worries about his condition. However, Yo Han tells her not to over react. Meanwhile, Seok Ki visits Tae Kyung.

Yo Han wants to go inside the center, but Seok tells him no one can enter the center under any circumstances. Yo Han goes inside the center despite Seok's opposition, and Si Young worries about him since the virus can be dangerous to him. Meanwhile, Yo Han keeps trying to diagnose the suspected patient's disease.