User blog comment:Zathronas/Speculative author: What is Cinder's plan?/@comment-96.254.157.84-20140807182116

I think someone mentioned Cinder having a traitor in Beacon before, well here's an idea: what if Pyrrha is the traitor and she said in the trailor's dance scene because she knows she's going to have to betray her friends soon.

I honestly don't believe it's true, but it is a fun plot twist. She is the most heroic and unlikely character to turn evil.