-N line

Min-su runs in order not to be late for work.
However, the subway time was faster than Min-su's time,
and Min-su, who took the next subway, arrives at a different place at a different time.
"Where is this?"
Arriving at an unknown place, Min-su witnesses his own past.
Where is this subway taking me? A dream? The past?
Leaving behind numerous questions, the subway passes by.