Seven years ago, Gu Yu and Chen Tingyu were each other's only friends.
Reunited seven years later, they looked at each other with strange eyes.
——No one can remember that summer, the parting, or why they forgot.
But Chen Tingyu always kept close to Gu Yu unconsciously, as if his body was more honest than his memory.
Gu Yu also found that when he faced this "stranger", his heartbeat would be inexplicably disordered.
They got to know each other again, were familiar with each other again, and were moved by their hearts again——
Until one day, a recording that was lost by two people at the same time was discovered.
A young man's crying voice came from inside:
"If I forget you tomorrow, will you still leave today?"
Purpose: belated reunion and reconciliation. The young man retrieves the lost memory and heart in the gap of time.