유아인 Oh Joon-woo Park Shin-hye Kim Yoo-bin 이현욱 Lee Sang-chul Jin So-yeon Elena Kim 김학선 Joon-woo's Father 소희정 Joon-woo's Mother 주보비 Joon-woo's Sister Jeon Bae-soo Masked Man 이채경 Masked Man's Wife 오혜원 Police Officer 전운종 Firefighter 손경원 Security Guard Infectee Lee Gyu-ho Fat Infectee Jang Ji-gun Ramen Commercial Model Yoo Yeon Sweater Middle-Aged Woman Jang Ui-don Veranda Glass Door Man Kim Hyun-woo SART1 Lee Seung-jin SNS Man Yang Mal-Bok Student's Mother