It is a fact of life that, inevitably, the Alpha Bitch has her moment of comeuppance. Just when this moment occurs, the last person you would expect, someone who has always been a loyal member of the Girl Posse, becomes The Starscream and turns on the Alpha Bitch at the perfect opportune moment, inadvertently aiding the heroes in the process.
Sometimes this is to take her place and become the [...] [tvtropes.org]