They clearly don't call it a "Hellcat" for no reason at all. The Dodge Challenger Hellcat sounds like Satan's pet feline decided it was going to gargle all the engines in the world, boiled in acid, and then scream out the resulting mix. It sounds scary.
I'm not sure I've heard any other car sound this raw, this powerful, this manic, this completely, positively juiced, in a long, long time. It's the kind of thing that would make children cry and their Brooklyn mothers send daggers your way. It doesn't belong in civilized society, and it doesn't belong near anything with a weak constitution.
In short, it's amazing.