Fourteen-year-old Alice moved into a fifty-year-old building. But something strange happened. She always heard strange knocking on the door at night. Alice's parents were very busy, so they were often not at home. She got up in the middle of the night to open the door, but found that there was always no one outside!
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No more spoilers = =.
This story is very simple and beautiful, and is by no means a thriller... Don't be afraid...
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