Marinette is walking to school with Alya, we have chemistry as our first class and the teacher is going to give us back the tests we have last week, both of them are really nervous, specially Marinette that didn't have much time to study due to her superhero duties.
In class Chloe arrived with her father, which was surprising, the teacher didn't mind much but started handing out the tests, Marinette didn't do as bad as she thought, Chloe got a 0 on hers as well as Sabrina, outraged she demanded the grade to change as she had the answers correct, but the teacher said that she caught her and Sabrina cheating so that was the grade they deserve.
"How can you say my daughter did anything like that, I will ask the school to fire you for this" said the mayor
"What I'm a good teacher that's why I want my students to learn and cheating is not a way to learn " the teacher said
"My decision is final now leave this place, before I do take more drastic actions " replied the mayor.

Alya and Marinette went to the bathroom afterwards they started to talk about what happened when the door sort of became wall and they were trapped, then by the window appeared a woman with a white coat and bright green hair that also made the windows become wall with some sort of chemical she had the two were completely trapped.
Marinette knew she had to step into action, but how without revealing her identity to Alya...
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Adrien was late for school, his father had him take a fast photo shoot before class, when he arrived he noticed there were no doors or windows everything was a big wall, something was wrong, so Adrien transformed into Chat Noir and climbed the school walls in order to get inside he saw what looked like a green haired witch with a white coat with different chemicals, the witch looked at him and said "hello chat, I am Chemiste are you ready to be turned to stone" and she tried to pour a chemical on him but as it fell on the floor it spread making the walls thicker.
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Marinette was scared she couldn't transform, she heard someone out Chat it had to be him, she was about to scream for his help when an earthquake happened and the walls started to become thicker, it was helpless to scream, she had to find a way to get out.
"Look  a window there at the top corner that woman must have missed it" Alya said
She was right, but there was no way for them to go up there, if Marinette transformed she could get herself and Alya out but was it worth to reveal her secret, or could chat handle on his own for now?