Piano tuner Lin Xiaoman has a taboo that he cannot touch - the Steinway that always stops in the key of B flat. Five years ago, after Cheng Yuan played the last out-of-tune chord on this piano, he disappeared from her world as if it had been erased. Until late at night during the rainy season, she found that the piano keys began to play their love song on their own, and a picture she had never seen before kept appearing on the bathroom mirror: Cheng Yuan was frantically knocking on a door without a handle.
When Cheng Yuan's "memory ghost" began to invade her reality, Lin Xiaoman realized that this relationship had never really ended. She must sneak into the memory maze built by obsession and retrieve the lost truth before the strings break. But the closer she got to the core, the more she discovered the terrifying fact: Cheng Yuan's farewell without saying goodbye was actually her own memory tampering in desperation.
Now, the man she had forgotten by her own hands was trapped in the black hole of memory, repeating the eternal struggle. To save him, one must face the most painful realization: some doors cannot be opened because they should not be opened, and some fevers cannot be overcome because they do not want to. When the last note falls, Lin Xiaoman will face the ultimate choice - to correct the memory and forget each other in the world, or to retain the scars and let love reborn from the ashes.
Purpose: True redemption does not lie in correcting the past, but in reconciling with the scars.