According to the Korean Film Council, the disaster film attracted 7.3 million viewers as of Sunday.
The film is about a young man who has a hard time finding a job and is put in a life-threatening situation where he helps people who struggle to evacuate from a city poisoned by toxic gas.
Some regard it as a mere time-killer but others praise its new approach to the disaster-based story by not being a tear-jerker.
The unexpected success of the film seems to be led by young viewers in their 20s and 30s who apparently sympathize with the story, as they may feel the same in reality amid a tough job market.
According to multiplex chain CGV, some 34.8 percent of its viewers in the second week of this month were in their 20s, compared to 28.4 percent for other movies.
The popularity of the film also shows that more people are drawn to light-hearted movies as life gets tougher. Even until two years ago, some serious films dealing with social and political issues were hugely successful. But since last year, films considered "easy" to watch have gained in popularity as moviegoers grow less interested in complicated or gloomy stories.
"Extreme Job", which attracted over 16 million viewers early this year, and "Aladdin" (12 million), both appealed to viewers of all ages with universal and easy-to-understand themes.
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