There is no escape from a tidal wave. During the busy summer months, the beach resort of Haeundae is packed with up to a million vacationers. On one such day, marine geologist Kim-Hwi detects some seismic activity which he believes will bring a mega-tsunami to the shores of Korea. Racing to alert the authorities, he meets his ex-wife and the daughter he never knew he had, when they see a massive wave coming their way.