Kang Dong-Goo dreams of becoming a movie director, but he is cynical due to bad luck. Cheon Joon-Ki wanted to follow in his father's footsteps and become an actor, but he is now just a minor actor. Bong-Doo-Sik came to Seoul to become a scenario writer, but things have not been easy for him. These 3 men run the guest house Waikiki in Itaewon, South Korea. Their guest house is facing bankruptcy and then a mysterious baby and single mother appear at Waikiki.

Martial law is declared when a mysterious viral outbreak pushes Korea into a state of emergency. Those on an express train to Busan, a city that has successfully fended off the viral outbreak, must fight for their own survival…