I love this movie. Yeah once you watched it and you know the truth…but I like to watch it sometimes.

I feel like
this is a spoiler even though we don't mention any details. And this is seriously one of those twists where the film will never be the same experience knowing it.

I have a certain dislike for those kinds of twists mostly. But sometimes I appreciate them a lot! I don't know what it is really, maybe I don't like Shutter Island because the twist is such a downer, you feel cheated about the character you were to supposed to sympathize with.

Has anyone seen the series or read the book Behind Her Eyes? My girlfriend showed it to me and...

I can't decide if I feel cheated, or if it's actually a really good twist. It's in the same vein as Shutter Island. But maybe even more out there.
I agree with your thinking about the twists and sometimes these makes the movies more and more complex to understand

No, I haven't seen these series or read the book but Thanks for recommendation. I'm going to try to find it and see it. :)
One mean Finn against the Nazis... Little bit of Tarantino + Rambo "First Blood". Slasher, heroic movie. I liked it. Revenge and retribution is unavoidable. Finnish Lapland landscapes are stark but at the same time beautiful.