来自首尔的哑语美术老师仁浩（孔宥 饰）来到雾津，应聘慈爱聋哑人学校。天降大雾，他意外撞车，维修时邂逅了人权组织成员柔珍（郑有美 饰）。仁浩妻子早亡，8岁女儿天生哮喘由祖母照看，所以他不辞辛苦谋职养家。然而，双胞胎的校长与教导主任竟逼仁浩索贿5千万韩元。同时，仁浩逐渐发现学校笼罩着一种紧张压抑的气氛，令人窒息。有三个孩子引人关注：聪颖的金妍斗（金贤秀 饰）、贪吃的陈宥利（郑仁絮 饰）和弟弟自杀身亡的全民秀（白承焕 饰），民秀总是满脸淤青。下课后，仁浩还听到女厕所中有呼喊与哭泣，在门卫的阻拦下他未深究。之后。他意外目睹了校长行贿警察，教导员毒打民秀，宿导溺罚妍斗的行径。一个惊天的隐秘被慢慢揭开，真相令韩国震惊…… 　　本片取材于2005年光州一所聋哑障碍人学校的真实事件，改编自韩国作家孔枝泳的同名小说。Gang In-ho, who is working to earn money for his daughter's surgery, is appointed to a school for hearing-impaired children in Gwangju. But what he discovers there is an ugly truth: the children are being physically and sexually abused by their teachers. When he decides to fight for the children's rights and expose the crimes being committed at the school, In-ho teams up with human rights activist Seo Yu-jin. But he and Yu-jin soon realize the school's principal and teachers, and even the police, prosecutors and churches in the community are actually trying to cover up the truth.