As we follow Calliope's story, we get a sense of mystery but we are unsure who to truly trust. This operates as an effective YA thriller with a few drawbacks. 

Pros: 
- Plot and subplot that work well together 
- the secret society inner workings make for a really interesting conflict 
- normal life is not ignored while all these plot twists are happening 
- the setting of the school works really well with allowing for the freedom of the plot, but not being unrealistic in what can happen for teen protagonists

Cons
- Too many reveals in the 3rd act. There are 4 or 5 major plot twists (depending on your definition of plot twist vs plot point) that all come into play within two or three short chapters
- One of the plot twists really undoes the stakes of the 2nd act