Actor Hwang Jung-min plays the role of Major General Chun Doo-kwang in the political drama film "12.12: The Day." Courtesy of Plus M Entertainment

The historical film "12.12: The Day," depicting the 1979 military coup, has become the year's second-highest-grossing local film and also ignited controversy, particularly among some conservatives.

While the film has been successful at the box office, it became the subject of debate following an sixth-grade class's plan to watch the film together.

The film's depiction of a significant moment in Korea's modern history has led to its inclusion in educational field trips. An elementary school in Seoul planned a field trip for its sixth graders to watch the film together to "deepen their understanding of historical facts and enhance historical sensitivity."

However, the plan met with backlash from some conservative YouTubers, who criticized the field trip and threatened to report the school.

After the fuss, the school canceled the trip, saying it accepted the various opinions suggested to the school despite its effort to "achieve educational goals" through the film, highlighting the sensitive nature of its subject matter.

Directed by Kim Sung-soo, who is known for helming the 1997 crime flick "Beat," the political drama film follows the intense nine hours of the 1979 military coup on Dec. 12.

When Major General Chun Doo-kwang (Hwang Jung-min) leads a group of military personnel to turn against the incumbent government and usurp power, Capital Defense Commander Lee Tae-shin (Jung Woo-sung) tries everything in his power to stop him.

The real-life historic coup helped military dictator Chun Doo-hwan, on whom the character played by Hwang is based, drive then-President Choi Kyu-hah out of office and led to Chun's eight-year military junta.

The film, which has been topping the box office since its opening, garnering a total of 6.38 million ticket sales as of Saturday.

In box office numbers, it beat the 5.14 million ticket sales of the crime film "Smugglers" and 5.57 million ticket sales of the Japanese animation "Suzume," taking the third spot in this year's top-grossing films, followed by Pixar animation "Elemental" with 7.24 million and local comedy action franchise "The Roundup: No Way Out" with 10.68 million.

A scene from the film "12.12: The Day" / Courtesy of Plus M Entertainment

The film has surprisingly garnered more popularity from younger viewers than older generations who lived through the time of the coup. According to cinema chain CGV, about 26 percent and 30 percent of the people who buy tickets for the film on its platform are aged in their 20s and 30s, respectively, making up more than half of the total viewers.

For younger generations, the film serves as a crucial, albeit dramatized, introduction to a significant yet not-so-familiar event that changed the direction of the country. Video clips explaining the political background of the coup and Chun Doo-hwan have surfaced on YouTube, garnering hundreds of thousands to millions of views following the film's release.

"I knew about it but didn't expect it to be this intense. Of course, it's not a documentary but a movie, so it has been dramatized to a considerable extent. But sitting there and watching the flow of events, my rage just continued to boil up," a moviegoer wrote online. "It's entertaining, yet infuriating."

The film tells an easy-to-follow story with quality production and a star-studded cast who give riveting performances. To recreate the look of a real-life figure, Hwang went through four hours of special effects makeup for every shooting, adding more reality to his powerful performance as a vilified dictator.

The film also features well-known actors like Lee Sung-min, Ahn Nae-sang and Kim Sung-kyun, as well as unexpected cameos from Jung Hae-in and Lee Joon-hyuk.

"I watched old documentary footage of Gwanghwamun Square and downtown Seoul in the early morning of Dec, 13, just after the military coup on Dec. 12," Jang Geun-young, the film's art director, shared in a release.

"There were tanks in the heart of Seoul, and unlike Seoul now, I felt a dense and heavy atmosphere. Taking this as a metaphor … it later became the visual concept of ‘12.12: The Day.'"