Big-budget Korean disaster movie. Haeundae Beach in Busan City on the east coast of Korea is a popular holiday destination for millions of ordinary Koreans, such as Man-shik (Kyung-gu Sol) and Yeon-heui (Ji-won Ha), who are taking a holiday together that they both realise could be the make or break of their relationship. But this summer they and their fellow holidaymakers are going to get a lot more of a summer adventure than they bargained for as a ferocious mega-tsunami - predicted by leading geologist Kim Hwi (Joong-Hoon Park) but repeatedly denied by the Korean authorities - heads their way, bringing with it death and destruction on an unthinkable scale.