A simple and quiet night in the streets of Shibuya, an old construction site with some suspicious people inside it. If we look carefully at the construction site, we could see a boy, age 18, standing above the half-constructed building. This boy's name is Torwa Amai. He is a spy who is currently studying at Miyora High. This is his 24th mission, and his goal is to rescue the mayor's kidnapped son, who is currently held captive in the construction site.
And there is a sniper 127 meters away in a building, aiming at the person standing beside the victim. The sniper fires, and Amai continues to get closer to the target. Another guy gets shot.
Then we see Amai pulling out the pin of a sleeping gas grenade and throwing it directly under the victim. The smoke spreads around the whole room, then settles to the spot. He starts by knocking out the guy who was trying to resist the gas. Then he tries to untie the hands of the victim. When he opens his mouth, the mayor's son starts to threaten him, saying that his father will not let him go and other rubbish.
So, Amai knocks him out with a chop, carries him on his shoulder, and escapes that place by running towards the lift and going down to the ground floor. Then he takes out a silencer, escapes, and heads to the junkyard.
Amai calls the manager to let him know that the work is done. A car arrives at the area, and he sends the son with them. He cleans all the proof and went to his room.
In the morning, he gets late to school. It is his graduation day. He goes to school and sees his teammates there. They talk about what they will do after high school. His teammate tells him where the girl got posted, but he doesn't know his location yet.
Then, at night, his partner calls him and says, 'Happy birthday, partner.' At the same moment, he gets a call from the manager. He quickly changes the call and asks what happened. The manager explains that since Amai has completed high school and turned 20, he has to shift to another city for missions. He will get assigned to another partner and has to get admission to college there. Amai agrees and sleeps.
In the morning, he starts packing his luggage and meets with his partners for the last time. In the evening, he says goodbye to the landlady and goes to take the apartment allotted by the agencies.
At night, he gets a call from the manager, who congratulates him and tells him that he has to examine the city before being allocated a mission. He is also informed that his new partner is in the city, but he won't meet them until the night of the mission.
The next day, he goes to college to explore it. He examines the ceilings and exits in the college and, in doing so, gets late to class. He doesn't want to be embarrassed on his first day of college, so he starts running. In the hallway, he collides with a girl.