I have so, so, so many thoughts about this novel.
I adored Hannah's first offering, The Nightingale. It was pitch perfect in terms of the setting, the context, the historical flavor, and the ending. And it was daring! In more ways than one - because it's tough to write something new about World War II any longer, and because it focused on sisters as the main characters (more about Hannah's ability to write strong female-focused narratives below).
I certainly think this novel is daring, but I don't think it is genius writing. There's something to be said for historical accuracy creating a solid base for a novel. You can always return to the "known" if your plot starts to devolve. In this novel, almost everything written seemed unpinned and untethered. As if they were complete flights of fancy, even though Hannah built this on the very real understanding of what it is like to live in Alaska, through all of its seasons (her own childhood background). So although she understood the setting - it was "known" - I think because she didn't precisely know the plot device - as I understand it, none of her childhood was destroyed by physical violence - this does not feel believable.
Of course, Hannah is working hard to craft very strong female characters. The problem isn't that the tragic story of an abused woman often showcases how difficult it is to be strong - that's a necessary part of the story, and I don't fault her for that. It's that the plot machinations of each of the women in the story do not seem realistic. It's hard for me to precisely pin down why, but I felt this throughout the novel.
If you want to learn more about what it's like to live in Alaska, absolutely this is the book for you. But be prepared for a bit of a wild ride, as a result.