If it wasn't for the ending!
This would be one of my all time favorite noirs!
The tension just mounts and mounts, and the sense of dread and terror wraps itself around poor Edward G. Robinson. And Joan Bennett is fabulous in this picture. She is a true beauty, and your heart just goes out to her in this scenario.
But then, seemingly out of nowhere, here comes that ending! Anything, ANYTHING, would have been better than what Lang came up with. Maybe this had the big advantage of not being a cliche back then. I don't know, but it sure doesn't work now.
And yet, I continue to be drawn to this picture. The set up is so well done, the cinematography is wonderful, the performances are uniformly superb, and Lang was clearly a master of mood and atmosphere. The Woman in the Window ends up being a worth while entry in the noir canon in spite of that ending.