Death Bell is a 2008 South Korean film. As the only Korean horror film to be released during the summer of 2008, it is the first film by former music video director Chang, who also co-wrote the script. Death Bell stars as Lee Beom-soo in his first horror film and K-pop singer Nam Gyu-ri in her debut role. Set in a Korean high school, the film's original title refers to the gosa, the important midterm exam that all students are required to take.
A group of 20 high school students participate in an elite class to prepare for the entrance exam. Among them are the rebel Kang I-na, her best friend Yoon Myong-heo and the clown Kang Hyun, who has feelings for I-na. After some strange incidents, the class is interrupted by a TV show about the best student, Min Hye-yeong, trapped in a glass that is slowly being filled with water. A voice in the PA system announces that the questions will be asked to the whole class; If he is not treated promptly, it will lead to death. He also warned them and their two teachers, Hwang Chang-wook and Choi So-yeong, not to leave school. The class was unable to solve the first problem to save Hye-yeong.
Despite the warning, the class tries to leave, only to find that a teacher and class supervisor, Mr. Lee, was beaten to death, leaving only Mr. Kim to protect them. The students separated and tried to answer the questions while trying to find a way out. Some of the dead students, then Beom, who had already tried to strangle I-na and was sent to a mental institution, escaped and tried to kill I-na, but Hyun protected her from an attack and died. Chang-wook then kills Beom. I-na is horrified to learn that Myong-hog was also kidnapped by a mysterious woman. They fail to save her, and Chang-wook strangles the woman to death.
A funeral ceremony was held for the students who died, after which Ina was kidnapped without being noticed. A final question arises: the man who killed his daughter will come forward and surrender. The person in question, who is now Chang-wook with amnesia, was revealed and killed by the brain, which turned out to be Mr. Kim. I-na is later released by So-yeong.
The flashback shows that Kim's daughter, Kim Ji-won, worked hard to enter the elite class. However, the parents of the dead students bribe Chang-wook to get the answers to the admission test, which gives them an unfair advantage. After being eliminated and discovering the truth, Ji-won confronts Chang-wook and he kills her to cover up her mistakes. The only witness to the incident, Beom, slowly goes crazy when he feels that Ji-won has haunted him ever since. Mr. Kim and his wife (the woman who hanged Myong-hog) decide to kill Chang-wook and all the students whose parents believe they are responsible for the death of his daughter.
The film ends with I-na seeing that she is at the top of the charts, and it is implied that Beom's attacks are due to her being possessed by Ji-won in the first place.
Lee Beom-soo as Hwang Chang-Wook
Yoon Jung-hee as Choi So-Young
Nam Gyu-Ri as Kang I-Na
Kim Bum as Kang Hyun
Son Yeo-eun as Yoon Myung-Hyo
Ham Eun-jung as Kim Ji-Won
Yang Ji-Won as Min Hye-Young
Kang Won as Song Dong-Hyuk
Kwon Hyun-sang as Cha Jae-Wook