I missed some, and I’m behind and saw 3…2…1 last night. I recall the HG Wells plot; whats-his-name un froze her to help with some nefarious plot. What did she do in between that episode and 3…2…1? How did she “go bad” working for warehouse 12, and what did she do to make Mike hate her so vehemently?
Thanks!
What made her go bad - her daughter died in a house burglary and she failed at going back in time to save her.
She kept trying to use artifacts from Warehouse 12 to find a way to change the past and eventually they realized that she wasn’t going to stop without radical intervention.
I don’t remember what she did to piss off Mika 
She manipulated things to find Warehouse 2, left Pete & Myka trapped there, and traveled back to the US with Poseidon’s Trident (or something trident shaped) in an attempt to set off the Yellowstone supervolcano and destroy civilization as revenge for the loss of her daughter. Myka managed to talk her out of it, but briefly quit the Warehouse because she came to doubt her own judgment.
Ah, thanks.