At 3:07 in the morning, Linjiang City Emergency Center operator Gu Lin received an alarm call from his mobile phone.
On the other end of the phone, he said only one sentence, claiming to be seven years later:
"Don't let Line 7 enter the terminal. Of the 312 people on the train, only one is still alive."
When Gu Lin called up the train monitoring system, he found that Line 7 had only twelve carriages, but there was an extra "Thirteenth Car" in the system that did not exist.
What made him even more unbelievable was that his father, who had been missing for seven years, was sitting in that carriage.
Since that night, strange rules that only a few people can detect have continued to appear in the city:
After midnight, don't respond to someone calling your name from behind.
If you hear children's songs playing in an abandoned hospital, you must leave immediately.
If you see a room without a door, use an old key.
Every time someone is saved, the future will be rewritten; every time it is rewritten, new rules will come.
Gu Lin and investigator Shen Qinghe pursued the case all the way, but found that all the mysterious calls pointed to the same day seven years later.
The person who made the first call was Gu Lin himself in the future.
