Into the Fire South Korean student Oh Jang-beom is a volunteer militia soldier during a battle in Yeongdeok, North Gyeongsang Province during the Korean War. As the city is overrun by the 766th Unit, 5th Division, Korean People’s Army He is dragged into a squad of South Korean soldiers led by Lieutenant Kim Jun-Seop attempting escape. The unit is eventually reduced to only Lt. Kim and Jang-Beom. A North Korean shoots and bayonets the lieutenant. Jang-beom is overwhelmed by terror and inexperience and is unable to save him. They are spotted by South Koreans and managed to get on one of the last trucks from the town and take it to an emergency hospital in Pohang. There, Lt. Kim is pronounced dead and a smug Jang-beom is seated beside him.
Capt. Kang commands Jang -beom, one of three volunteers with combat experience to lead the newly-recreated student soldier unit. Three young criminals who are led by Ku Kapjo, are part of the group and begin to destroy students’ food supplies. While on patrol the area, they are attacked by a KPA sniper who leads them to an ambush. Before disengaging, the students sustain heavy casualties. Morale of the students is shattered by the disastrous encounter. Capt. Kang and ask for help, but regular forces are confined to the Nakdong River. Kang asks his superiors to help him however, they deny it. Kang is permitted to leave, however they allow him to travel in vehicles and a small contingent of South Korean soldiers to help the school. Into the Fire HD
One of the student-soldiers, Dal-Young, is captured by the 766th Unit and is interrogated by Major Park Mu-Rang. Mu-Rang feels sorry for this student and instructs the student to return to his school. He’ll also go there to evaluate the strength of the students. In the school, he informs Jang Beom that the group will, in 2 hours, capture the school, and offers to spare the attackers’ lives if they raise a white flag. Kap-Jo beats Dal-young and then fights Jang Beom. He leaves with a friend, Chang-wu, for the Pusan Perimeter. After leaving, the two encounter an North Korean truck filled with weapons and other supplies, which is stuck in a road.
The remaining students get ready to defend the school, by raising not a white flag but the South Korean national flag and Major Park makes his own preparations for the assault. The attack starts and the students could cause serious casualties to North Koreans but are eventually forced to retreat. Suddenly the North Korean supply truck roars in, driven by Chang Wu and Kap-jo, carving their way through the North Koreans, halting their assault and also bringing valuable heavy weapons to the students.
The 766th’s men are able to enter the school under the cover of tanks and take out the majority of students. Jang-Beom and the Kap-Jo battle to take on the North Koreans inside the building until they reach the top of the building, where the others have fitted machine-guns. Jang-beom, Kap-jo and others try to stop the North Koreans from reaching the roof.
Just as Kapjo and Jangbeom run out ammunition and the Capt. Kang as well as the South Koreans arrive. They take out the North Korean tank and steadily beat the North Korean infantry in the school grounds. On the roof, as Jang-beom is stricken with exhaustion and his woundsare healing, Major Park arrives and kills Kap-jo. While Park exults, Jang-beom humbly loads his rifle and shoots Park the same way as Park is also shot at. Later Capt. Kang. Jang-Beom is slain by his wounds while Kang soothes him.
It is revealed that out of the 71 students, only 48 were killed while protecting the school. The film concludes with a flashbackof an Army photographer taking a group picture of the students-soldiers prior to the regular troops depart for Pusan and the remaining veteran students, who are now aged look back on their experience.