While a zombie virus breaks out in South Korea, passengers struggle to survive on the train from Seoul to Busan.

Small-town girl Deokee is abandoned by university professor Hak-kyu after a lusty affair, and vengefully approaches him 8 years later when he starts suffering from blindness.

A girl wakes up in a secret laboratory and meets Kyung-hee, who is trying to protect her from a gang. When the gang finally finds the girl, they are overwhelmed by an unexpected power.

In this competition of intelligence, contestants face off in games of wit and strategy to be crowned winner and go home with the ultimate prize.