The Sinister Substitute Scholastic Inc.

Kamala, Doreen, and Miles are back at Avengers Assembly for a new semester! When Captain Marvel announces she's adding staff to the school, the students aren't sure who could possibly join - but it looks like Cap went above and beyond, and the school is full of new teachers!

With all these new teachers, it's hard to keep track of who's teaching what, and what they're supposed to be learning. And some of these teachers are really not acting like heroes at all, but more like... super-villains? All that new staff has created a lot of confusion that is ripe for exploiting! Someone is impersonating students and teachers, using lies and deception to break up the new generation of heroes. Can Doreen and her friends get to the bottom of this scandal? Or will this be the end of the Avengers Assembly?