The energetic zombie flick "Train to Busan" attracted more than 10 million viewers as of Sunday, the 14th domestic film to achieve the feat.
The Korean War film "Operation Chromite" has already pulled in over 5 million viewers, while epic "The Last Princess," attracted more than 1 million in its first four days.
According to the Korean Film Council, 26.2 million movie tickets were sold last month, up 11.9 percent from the same month last year. And 15.77 million were for domestic movies, up 40.4 percent.
This has raised hopes that more than two Korean movies could attract more than 10 million viewers this summer, outdoing last year's double coup with "Assassination" and "Veteran."
"Train to Busan" was not seen as a major contender even until the beginning of this month, because Korean viewers had not so far taken zombies to their hearts. But perhaps to its skillful blend of disaster movie, zombie horror and family values, it has become a hit.
"Operation Chromite" noisily appeals to patriotic audiences who are undeterred by the poor reviews and celebrates the unsung heroes of the famous Incheon Landing that turned the tide in the war.
"The Last Princess" is also winning over audiences with a combination of melodrama and history.
But Korean movies failed to account for a majority share in the first half of this year, ending up with a 46.3 percent stake. They were beaten by standard Hollywood fare like "Zootopia" and "Captain America: Civil War,” though "Jason Bourne" and "Suicide Squad" did not do as well as expected.
The start of the Rio 2016 Summer Olympics in Brazil has so far had little impact on ticket sales as most events were held in the early morning hours Korean time.
The record hot weather is also having a positive impact on ticket sales. Movie industry analyst Kim Hyoung-ho said, "Theater attendance rises on days when the mercury soars above 30 degrees Celsius, particularly for Korean-made movies."
Air-conditioned theaters provide an easily accessible refuge, and people who are pressed for time tend to choose films with a clear message, which tends to favor mainstream Korean films.