Backstage among the teachers.
"X Chronicles? Is there such a thing in a children's play?"
"I have no idea, sounds like something from a cartoon, right?"
"Mr. Fang, what exactly is your class's act? You kept it very secret."
"Uh... it should be a science education-themed play, I guess."
"Science-themed play? Is there even a category like that in plays? Mr. Fang, the way you choose acts is quite out of the ordinary."
"Cough! Well... we can't kill the kids' creativity and enthusiasm for participating, right?"
Amidst the murmuring, the stage curtains slowly opened, revealing something to the audience... A door?
A slightly rough mechanical double door made of cardboard appeared, with a sign that had "ACE2" written on it in black marker.
At the same time, a female voice-over came through the speakers.
[Our body is like a vast city, and each cell is a factory within it.
The normal operation of the factory is essential to maintain the regular functioning of the city...]