This discussion may contain spoilers!
It must seem TERRIBLE of me but since episode 1 I've suspected Snow. She never seems very shocked or seems to know more information than she lets on... Now her change from innocent white clothing to... Black... Well... My suspicions are just growing and growing and she's becoming more controlling. Then Nerissa said to watch your friends or something, and at the beginning of the latest episode, Dr. Swineheart told Snow to make Bigby rest and she pretty much ignored him and pushed her way of doing things, which put Bigby back onto the front lines.
I think Snow is a control freak whose being corrupted by power, like Crane. I think she's in on it in some way - any way. Maybe even a small way