Maybe especially if she's very secretive and cunning and no one knows or even suspects that it's her, and they can't figure out what's going on and are afraid that the government has taken over River's brain or that there's a stowaway on the ship who's picking people off, and Kaylee's acting totally normal and innocent about it all, and then in the end she's the only one left and takes the ship and flies it, like, square on into a planet or something.
no subject
...cough.