The Secret Room of Qichi Garden

Antique dealer Lu Wenzhou died in his study room. The door was locked from the inside. There was only one key, and it was lying in his own hand. This was his lifelong rule: one more key means another vulnerability, and he never wanted a second one. But when everyone was helpless about this secret room, the young girl Lu Zhiwei discovered the only exception to her father's iron law in an old pocket watch and a secret room that only two people knew about. The secret room has never been "cracked" because what the murderer holds is a real key that no one knows about.