Difficult to know what to say without any spoilers as the plot says enough. However, I have never been more engrossed in a movie than in this one. I felt as if I were in the tunnel with him. The tension kept me on the edge of my seat, full of emotion.
Superb acting I almost forgot I was only watching a movie.
South Korean and Asian movies are far better than western productions and I am sick of hollywood nonsense. Watch this and perhaps you will understand my opinion more.