First, I need to confirm which film they're referring to. There's a 2011 South Korean film titled "Silenced" (also known as "Silenced, based on the novel "A Good Rain Knows How to Fall"), directed by Hwang Dong-hyuk and written by Gong Ji-yoon. It's about a teacher who investigates a case of school bullying and systemic cover-ups by authorities. It's a serious film that sparked a lot of discussion in South Korea regarding real-life educational issues.