1962年，一個充滿禁忌的時代。翠華中學高三女生方芮欣與輔導老師張明暉展開師生禁戀；張明暉卻暗地與師生組織讀書會研讀禁書⋯ 某日，張明暉人間蒸發，方芮欣和高二男生魏仲廷決定回校尋師，卻發現校園已變荒涼鬼域，軍官追魂清算，學生連遭殺戮，方芮欣更墮無限輪迴為求真相⋯返校尋師，結果屍像橫生？誰要負責任？

In 1962, a sense of desolation and tension permeate the society. Fang, a twelfth grader at Tsuihua Senior High School, falls in love with Zhang, a counselling teacher. Troubled by the problems at school and home, Fang feels that Zhang is the only person who understands her. Longing for freedom, Zhang forms a study group with his colleagues and students, including Yin and Wei. Reading the banned books allows them to be liberated for a brief moment but at the same time, they put their lives in great danger. One day, Zhang vanishes into thin air, and only Fang and Wei, an eleventh grader, remember him. Together, Fang and Wei start looking for the disappeared teacher but find the school gradually slipping out of the world they are familiar with. Then in a realm dominated by ghosts and spirits, the pair are forced to face the terrifying truth…