Cosby certainly did some dark stuff, for which he was locked up and released on a technicality. Did he do any dark comedy? I only remember the dire Cosby show.
Heath Ledger was a very ordinary, unassuming actor who metamorphosed into something quite extraordinary as the Joker, managing to convey extreme malevolence. I wonder if he came up with the lip licking himself?
and ALL his standup routines are simply the prototype for Samuel L Jackson in Snakes on a Plane. MF this, MF that, MF the other, MF, MF something else.