Episode 1

Assassination Time is the first episode of the Assassination Classroom anime series. The episode first aired on January 9, 2015.

Overview
Class 3-E of Kunugigaoka Junior High School is the left-over bunch of misfits of the school who's homeroom teacher is the creature that blew up 70 percent of the moon, turning it into a perpetual crescent and plans to do the same to earth in a year's time. The Japanese government tasked them with assassinating their teacher before that happens, with a reward of 10 billion yen on the line.

Summary
The students of Class 3-E are nervously awaiting the arrival of their homeroom teacher who is currently flying to school at top speed. Soon, he lands in front of the school building and makes his way to class. Once there, he sets the rollbook on his desk and calls for homeroom to begin, telling the student who was on welcome duty to call the command. Nagisa calls it and everyone stands ready with their firearms and begin fire when he calls "Bow!". The teacher dodges the bullets and begins taking roll.

After roll call is finish, the teacher expresses his happiness as there are no absences and the students begin complaining about how he's too fast and that shooting at him all at once doesn't work. The teacher comments on how a single bullet didn't hit the mark and that strategy that relies solely on numbers lack individual thought and that the students need to be more creative or else they'll never be able to kill him at his maximum speed of Mach 20. The students start complaining again, saying that the bullets are just BB pellets and that there was no way he dodged them seriously. The teacher then asks for them to gather up the BBs and give them to him, and he proceeds to shoot one of his own tentacles off to show that the BBs do in fact harm him even though they're harmless to humans, but given a few seconds and he regenerates. He also tells them that regardless of the fact the BBs are harmless to humans, they could injure themselves so no shooting in the classroom unless they're trying to kill him. He then proceeds to mock them saying that he does hope they can kill him before graduation. After, he tells the students to put the guns and BBs away and calls for class to begin.

Class has begun and the teacher is in the middle of the English lesson. He asks Isogai a question and he correctly answers the question. While continuing, Kaede whispers over to Nagisa and shows him the crescent moon outside the window. This prompts Nagisa to wonder and think back as to how him and the rest of Class E ended up in this situation, noting that two things happened at the beginning of their third year:

The first thing was the moon suddenly exploding into a crescent, which caused for breaking news report for it all over Japan. The second thing was the creature who destroyed 70 percent of the moon appearing in Class 3-E, declaring that he'll do the same to earth in a year's time, stating that he's now their homeroom teacher and prompting the entire class to feel that there were at least six things wrong the situation. A man from the Japanese Ministry of Defense then introduces himself as Karasuma and tells the class to understand that what he was about to tell him was top government secret. He's blunt and tells the students that he wants them to kill that creature, surprising them. Mimura breaks that surprise by asking if the creature was the alien that came to attack them. The creature is offended and claims that he was born and raised on earth. Karasuma states that though he can't discuss the details, the creature is telling the truth and that next March, the creature will destroy the Earth like he did the moon. He tells the class that only the world's leaders know about this and that if news of the creature gets out in public it'll cause a global panic and that they have to kill him in secret; in other words, an assassination.

Karasuma pulls out an Anti-Sensei Knife and begins attacking but, the creature is incredibly fast and while dodging begins to meticulously trim Karasuma's eyebrows. He explains that that the the creature is a super creature who can turn the moon into a crescent and has a max speed at Mach 20 and that if he gets away, earth will be left helpless, awaiting its destruction. The creature closes his eyebrow trimming kit and states that just destroying the earth isn't fun so he made a deal with the government: No killing him and instead he'll teach Kunugigaoka's Class 3-E. Karasuma states that they don't know his reasons, but they were forced to agree on the condition that he doesn't harm any of the students and that there were two reasons: First, if the creature comes to a classroom everyday then the government can monitor him. The second was that it gives thirty people the chance to kill him from an extremely close range.

The flashback ends as Nakamura tries to shoot the teacher. The teacher scolds her and tells her to not let assassination interfere with her studies. She apologizes and the teacher tells her to go stand in the back. Nagisa begins thinking back again with unanimous questions from the class that were faded with the final condition of the assassination: A successful assassination will be rewarded with 10 billion yen. It was only right as a successful assassination would literally save the earth. Karasuma tells the class that luckily, the creature doesn't think much of them. The creature's face is now yellow with green stripes and Karasuma explains that it means he's mocking them. The agrees and says that if the government can't kill him, how can the students and that the government even sent their best fighter jets, but he ended up giving them a midair wax. Karasuma tells the class that they must find an opening in his defenses and strike at it and that they will be supplied with weapons and ammo that won't harm humans but'll harm the creature. He also tells them that they must keep this a secret from their friends and family and that there's no time to lose. The creature then tells the class to let's make the most of their remaining year. The flashback ends once more with Nagisa noting that they only have one year and that if they don't manage to assassinate their teacher, the earth will be destroyed.

The lunch bell sounds and the teacher says that he's going over to China to have some Mapo tofu and if anyone wants to assassinate him, just call him up on his cell. He leaves at Mach 20 and the students calculate that it'll take him about 10 minutes to get to China's Sichuan province, the home of Mapo tofu and note that no missile probably could shoot that down. They begin to note at how the teacher, referring to him as an "octopus", even grades paper while going faster than the speed of sound and that he's really good at teaching. Mimura then says that regardless they are Class E and Okajima adds in that no matter, trying hard won't do much. Nagisa notes that the super octopoid teacher and their assassination target was, for some reason, a really good teacher. They were normal students apart from being impromptu killers, but Class E is a little different from the rest. Terasaka then calls out to Nagisa and tells him to come with him and his friends so they can go over their assassination plan.

Outside, Nagisa goes over his observations of the teacher that Terasaka asked him to do. When he was about to go into another observation he made, Terasaka states that he doesn't need to know all that and that he has a plan: When the teacher lets his guard down the most, Nagisa is going to carry out the plan. Nagisa is hesitant and Terasaka tells him to not be such a goody-goody; they are Class E, the misfits of the famous prep school that is Kunugigaoka, calling them the E-as-in-End Class. Every day the people of the main school sends them to isolated mountaintop campus and discriminate them like their trash and because of that, they could possibly never get another chance like this one to earn ten billion yen. Terasaka takes out a small draw-string bag and gives it to Nagisa and tells him to not screw up. Nagisa then thinks back to when he was dropped to Class E. While thinking back, he hears the sound of his teacher flying who lands in front of him, holding a missile. He asks his teacher why he has that and he replies that the Japanese Self-Defense Force ambushed him in the Seas of Japan. Nagisa says that it must be terrible to be target to which his teacher disagrees, saying that one knows their powerful when everyone has it out for them. He then begins to head inside, saying that it's time for fifth period to begin. Nagisa reluctantly says yes and thinks to himself that his teacher doesn't understand. If one if everyone's assassination target that means they acknowledge their power and that a creature like that wouldn't understand what it's like to be unworthy of anyone's expectations, fear, or even their recognition. He thinks back to what his old teacher said to him once he got dropped to Class E and then thinks that he may be able to kill the creature that is his teacher and that that teacher probably doesn't even see him.

Fifth period has begun and the teacher tells the class to compose a short poem to go along with their theme and that the final line should end with "was tentacles all along" and that when their finished to bring them to him for he'll be checking for proper grammar. He recite an example and tells the class that afterwards they could go home. Kurahashi asks him how were they supposed to write about that and the teacher asks them if any wonderfully slithering phrases are coming to mind. He proceeds to "slither" and Maehara tells him to cut it out. Kayano then calls out to ask a question and asks the teacher what his name is and that how will they know what teacher they're referring to. The class note that the teacher never gave it to them. The teacher tells her that his isn't really the kind of name one tells a person and to go ahead and give him one, but for now she should focus on her schoolwork. He then goes into a little "break" and his face turns light pink, signaling that he's tired. Nagisa gets up with his poem in hand and steadily walks over to him, hiding a knife along the folded paper. He begins noting that after lunch, around the time everyone gets sleeping, the teacher's face sometimes goes light pink and that he was even a little slow responding to Kayano's question and that this might be when he's most vulnerable. He then notes that they prep-school failures are always thinking, "we have to get back at them somehow" and that they were always told that they could do it if they tried.

Once he reaches the teacher, he pulls out his knife and strikes only to be stopped. The creature then tells him that he said be more inventive and at that moment Nagisa reveals the grenade and latches on to the creature thinking that they have to prove themselves by any means necessary. Terasaka pushes the button that makes the grenade go off and BBs fly everywhere. Terasaka, Muramatsu, and Yoshida begin cheering and the other students go off at him asking what did he do [to Nagisa]. Terasaka tells them that he gave Nagisa a toy grenade but filled it up with three hundred anti-sensei bullets at high speed. He states that it's not strong enough to kill anybody, but he'd use his ten billion yen to cover Nagisa's medical bills. He discovers a thick membrane covering Nagisa and the teacher's voice is heard, telling the class he sheds his skin once a month, using his old skin to protect Nagisa. The creature reveals himself on the ceiling with air turning ominous as his face begins to turn pitch black, signaling that he's furious. He then speeds out of the room and throughout the town at Mach 20 and comes back with Terasaka, Yoshida, Muramatsu, and the rest of the students' house nameplates. He threatens them by saying though he made an agreement with the government to not harm them, they never said anything about their families and that if they try another assassination like that one he may just kill their families and friends, or rather the whole planet apart from them. Nagisa notes that five seconds and the class knew; there was know running to the ends of the earth for them and that if they really wanted to run, they would have to kill their teacher.

Terasaka goes off and calls the teacher a pain, asking him what's wrong with using an annoying method to kill such an annoying target. The ominous air suddenly disappears and the teachers face is orange with a circle telling them that plan wasn't annoying, rather it was a very good one. He especially praises Nagisa for keeping his movements natural until the very end. He also reprimands Terasaka, Yoshida, and Muramatsu for not looking out for Nagisa and to Nagisa for not looking out for himself. He says that students like that aren't fit to assassinate anyone with his face turning purple with an "X" to emphasize his point. He tells the class that they need an assassination worth smiling about, one to be proud of and that they're all capable assassins who have that power within them. Nagisa notes that being chewed out at Mach 20 then praised with waving tentacles, that this unusual education made him pretty happy and all because that unusual teacher was looking at them head-on. The teacher notices a piece of sizzling wood on his desk and thinks back. He's holding a woman who's bleeding and telling him that she wants him to teach those children [Class E] and that with those wonderful tentacles of his he'll surely be a wonderful teacher. He then puts the wood out and asks Nagisa a question: He doesn't have the slightest intention of being killed; he will enjoy his time with them until next March and then blow up the earth. If he doesn't like it, what will he do about it? Nagisa notes that they've never assassinated someone before and that there's plenty of other stuff they should be doing, but he feels that even that teacher will except his bloodlust. He then tells him, with a smile, that before he destroys the earth, he will kill him. The teacher has his mocking face on and tells him to go on and do it, telling the class that once they kill him, they can go home leaving the class in disbelief. Nagisa heads back to his seat once more noting that they they are killers and their target is their teacher. Kayano begins thinking about how their teacher is unkillable, prompting the name "Korosensei" with Nagisa stating that it's them and Korosensei in their assassination classroom.