Son Ye Rim's accident in the lab leads to a very dangerous discovery. Sgt. Yong Dong Jin is unaware of the real danger and goes missing during his mission in the DMZ.

The search mission returns with the body of Corporal Oh and a casaulty after an unexplainable event happened to them. It also caused some panic with higher ups with potential consequences for Sergeant Yong's military discharge.

A standard patrol in 1997 goes wrong with a North Korean defector in the DMZ. In current day, a search party is scrambled when a South Korean soldier goes missing in the DMZ.