The Vanishing Hammer

New employee Zhou Qin moves into the factory dormitory, where Zhao Yingying shockedly recognizes her as the 'missing roommate' from her memories, though Zhou Qin and her fellow workers deny it. Late at night, a shadow wields a hammer, chanting 'eighty' while attacking Zhao's bed, yet the victim is the person in the neighboring dorm. Subsequently, Zhao is chased by a short-haired woman with a hammer, while Zhou is bathing. Suddenly, someone knocks urgently on the door claiming to be 'Zhou Qin', but the person inside turns out to be the dorm manager. The manager is later attacked and killed in the corridor, with the gruesome manner of death eerily matching the nightmare Zhou had the night before, where she screamed, 'Smash you to death!' A photograph of the crime scene reveals a woman with Zhou's appearance, making the truth increasingly mysterious.