King has a knack for giving us some real creeps and scary baddies, and Percy and Wild Bill were certainly fine examples of such.
Don't want to spoil anything for anyone who hasn't watched it, but I thought the reveal re: WB at the end was a little uneven in tone. Maybe it's just that Sam Rockwell has a likeability even when he's playing despicable characters, but there are some almost comedic moments with him, even when he's raising hell, and the reveal at the end was... well, anything but comedic.
I don't suggest Rockwell's performance was comedic, just that there were a few times where you couldn't help but laugh at some of his antics. That was hard to square with the feeling at the end. Tho, that's life, too. Perhaps by design.
Just my two cents! I thought both performances were top notch.
It took me years to give Andrew Robinson a chance in any other role, so convincingly creeptastic was he as Scorpio in Dirty Harry. I'll likely have the same thing with Jack Gleeson, who plays the insufferable sadistic git on Game of Thrones.