I think not disturbing per se, but ‘On GP’ by Death Grips is a good contender. From someone who always speaks so esoterically, it felt like a genuine cry of help from Ride, which sent chills through me.
Besides that, probably ‘Dance With The Devil’ by Immortal Technique, ‘Aw Yeah? (InterVENTion)’ by Tech N9ne, or ‘The Tower’ by ICP (yes, that ICP, I know).