From memory, I thought the progression in the first section went a bit like Cm, F, Cm7, F (repeat) then AbM7, Bb and back to C minor, essentially. I would say that is at least the skeleton of it (though there's obviously some held notes, parts of the strings & counter melody, etc. that I'm not factoring in.) To be honest it doesn't sound too unusual in the earlier parts. The chromatic parts in the last section are way more interesting to me (and great
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