I was almost let down when Jane’s dark secret was that she didn’t do anything to help her evil foster father. She didn’t kill him, she just failed to help him as he died of natural causes. And that’s basically the least evil thing anyone in this novel has done, with all the murder and framing other people for murder! Jane’s just hoping to weasel her way into being a Thornfield wife, because she wants a comfortable life without so much struggle, meanwhile Bea commits murder twice, and frames ol’ Tripp for it, with Eddie as a second possible fall guy, and she’s pretty clearly planning to off Jane and Eddie, too, if she needs to. Jane’s barely even evil! And she’s the only one who seems to feel even a little guilt!
Also, for a lot of the The Wife Upstairs, I was worried that Jane was heading for trouble if she eloped with Eddie and he found out that wasn’t her real name… and all her secrets came out… but that was all sorted out because she had Helen’s ID.