Stairs, upward is the direction of the sky, downward is the direction of home.
The stairs they walked through during a power outage during overtime work actually brought Su Xia and others to another unknown world.
At the wrong time, she met the person she cared about the most.
She appeared in his life in the most unlikely place to be together.
"I promise you, I will accompany you through every staircase and take you home."