The Guard Post (GP 506 in South Korea) is a 2008 Korean horror film written and directed by Kong Su-chang.

Later, in their car, Noh's friend informs him of an assignment that the military has ordered him to do: head to Guard Post 506 in the Korean DMZ to investigate a strange incident there.

Noh reports to his superior on the phone, who wants him to bring Yoo back, despite his objections as the investigation has not been completed yet and will be forced to end once the clean up crew arrives in the morning.

In the present, Doc is unable to find any cold medicine in the post first aid room which supposedly should have sufficient amounts of it.

Kwon gets tied up and thinks back to the time where the real Yoo was blamed for infecting the entire platoon with the mysterious virus.

Meanwhile, Kwon, tied up in the generator room, struggles with his bonds and knocks out the electric supply temporarily, blacking out the bunker.

Later, while staring at the rain outside, Noh touches his family photo and comes to a terrible resolution: He decided to kill everyone alive including himself to stop the virus.

Eventually, only one Private is survived and as he opens the door to escape GP 506, his act triggered the booby trap installed by Noh, killing him and ravaging the area with explosion and fire.

The movie then focuses with the last recording made by Corporal Kang explaining about the virus and the disease, as well as the way to solve the disaster: killing everyone alive in the 506.

It ends with the scene in which he brings the cake topped with burning candles to the barrack, and soon after shooting with his gun to kill everyone.

A review from Twitch said that The Guard Post is not as strong as Kong's first Korean horror film R-Point as the depiction of flashbacks and the present was confusing, though the story was interesting.

[3] Screen Daily notes that The Guard Post is similar to Park Chan-wook's film Joint Security Area but with an emphasis on horror rather than geopolitics.

[4] However, it is recommended for its well-defined plot which is rare to zombie films and its well-rounded characters and slick production values.