Since her sister accidentally fell into the water and died four years ago, Jian Mo has been living in a daze. Until the day of moving four years later, Jian Mo accidentally found a smartphone that did not belong to her sister in her relic box. What surprised her even more was that it was herself four years ago who answered the phone, and the time was exactly the day her sister died! Jian Mo persuaded herself four years ago to help her sister avoid death, but her sister kept falling into new crises. At the same time, the phone battery was running out, and the mastermind behind the scenes also quietly took action...