Graduation Trip and a Sea of Sunflowers

It was a graduation trip after the college entrance exams. Even the classmates who had gone abroad to study returned from the other side of the world. Soon, everyone would go their separate ways, and chances to meet again would be few and far between. But a string of murders cast a terrifying shadow over what should have been a memorable trip. Then a mudslide blocked the only road back, forcing everyone to face the truth: both the next victim and the killer were among us.