The M3 patients are isolated in the Medicube's ICU. Myung Joo takes a turn for the worse.

Cast: Song Joong-Ki, Hye-Kyo Song, Jin Goo, Kim Ji-Won, Ahn Bo-Hyun, Jasper Cho, Woong Choi, Park Hoon, Jyu-ni Hyun, Jo Jae-yoon, Seo Jung-Yeon, Byeong-cheol Kim, Seung-Joon Lee, David Lee McInnis, Kim Min-Suk