Overview
Assassination Classroom is a 2015 Japanese school science-fiction action comedy film directed by Eiichirō Hasumi and based on the manga series of the same name created by Yūsei Matsui. It was released in Japan on March 21, 2015. A sequel titled Assassination Classroom: Graduation was released in 2016.
Plot
The movie opens with the Japanese military's failed attempt to capture whoever it is that has destroyed over 70% of the Moon, which sees the entire squad sent to capture it being attacked by a mysterious tentacled being.
Meanwhile, Nagisa Shiota, a ninth-grade student of Kunugigaoka Junior High School, narrates of how he came to be sent to the situation he is in: he is included in Class 3-E, which is reserved for delinquents and other undesirables of the school and is a laughing stock among the school. However, Class 3-E is actually a cover up for the Japanese government in their attempt to kill Koro-sensei, a tentacled mutant creature that apparently is responsible for the Moon's destruction. The students have to assassinate him before graduation, the time when he plans to destroy Earth, using special knives and BB pellets, but at the same time also have to study both academic and assassination disciplines from him. In teaching, Koro-sensei is assisted by the government-affiliated Tadaomi Karasuma and Irina Jelavić, a Serbian assassin.
Despite being fully aware that he is their ultimate target, Koro-sensei is able to bond with Class 3-E, who in turn regard him as their indispensable teacher. When asked why he took the job, he says it is done to fulfill a promise made to someone. Throughout the school term, Class 3-E welcomes three additional students: Karma Akabane, who has recently come out of his suspension due to protecting a former Class 3-E pupil from being bullied by Class 3-A students; "Ritsu", an AI-box displaying the form of a girl; and Itona Horibe, the also-tentacled self-proclaimed "blood brother" of Koro-sensei who is carried away from the school by his cloaked guardian after losing a match against the latter. At one time, Karasuma's position as P.E. teacher is briefly replaced by his rival, Akira Takaoka, a drill instructor-esque individual. Karasuma is then challenged by Takaoka to send a student to attack him with a tap of the knife. Karasuma then sends out Nagisa who successfully plants the tip of the knife on Takaoka, thereby expelling him from the school.
From Wikipedia (CC BY-SA 4.0).