Behind the iron door of the clinic in the abandoned hospital, there is a rusty lock that has not been opened for thirty years. The tooth marks on the key have long been smoothed away, but the echo in the lock cylinder has never stopped.
The sister of intern Chen Mo disappeared here three years ago. In the last phone call, apart from her breathing, there was only a "click" of the iron door locking. In order to find the answer, the moment he pried open the consulting room, the sound entangled him - it sounded at midnight every day, like someone turning a rusty lock in his ear, and the distance shortened inch by inch.
He dug out the yellowed medical records from the dusty drawer and said, "Don't look back when you hear the lock cylinder turning." The date of signing was exactly the second day of the "medical accident" twenty years ago. And all the people who came into contact with this medical record eventually became the new soil of the unknown grave in the backyard of the hospital, and even the bones smelled of rust.
Mr. Zhou, a retired nurse, looked at him in the shadow of the grocery store. He handed over an old key with a vague name engraved on it, and said: "Some locks are more terrifying when they are opened than locked." But Chen Mo couldn't stop - he found that he in the mirror was slowly turning into the person in the medical record photo, and in the voice recorder left behind by his sister before she disappeared, in addition to the sound of the lock, there was also his own voice saying: "Lock the lock and don't let it come out."
When the rusty lock finally turned in his hand, what exploded in the echo was not the truth, but the screams of those who were buried alive behind the wall twenty years ago. It turns out that the lock was never to prevent outsiders, but to trap the "thing" that climbed off the operating table - and he had long since become the new key.
