Just about any of the four main characters on Seinfeld, but especially George Costanza.
Black Jack Randall, Outlander. Holy God, that man is pure evil.
ZipperJJ:
I didn’t see any redemption. He was rotten to the end. The writers may have attempted to assign to him some noble motivations, but ultimately, everything he did was through cold manipulation of other people.
Falconetti off Rich Man, Poor Man. A nasty piece of work.
I’m sure I could think of more evil characters, but Vee Parker in season 2 of Orange is the New Black sucked. She manipulated our favorite characters and brought down the mood of the whole show.
Syler from Heroes
Dr. Smith from Lost in Space.
Or… Gilligan 
I honestly couldn’t remember the exact details of his story line, so this information makes him even more evil for purposes of this thread. Thanks! 
Garret Dillahunt in both of his rolls in Deadwood: Jack McCall and Francis Wolcott. Both were amoral, murderous psychopaths with zero to redeem them. Dillahunt was brilliant in both rolls.
I just found him despicable. He was a cop-- a “good guy”-- but I found him less honorable than many of the guys in the game. His motivation for solving crimes was never about doing the right thing, but rather winning. Very self serving asshole. And when he was in “win at all costs” mode, he fucked everyone around him.
Well sure, but he was merely a cosmic wuss (and it turns out near the end a perv). Gendo and Ritsuko, OTOH… The crimes against humanity trial would last several lifetimes…
AAAahhhh, Miiister Mordenn… Nah, come on: Bester!!!
I don’t use websites that make me read a Terms of Use agreement and agree to policies “should you pursue a claim”. WTF is up with that?
Vern Schillinger from OZ.
Adebisi and Schillinger on “OZ”.
(How did Adebisi keep that little hat on his head, anyway?)
EDIT: LOL, ninja’ed.
He was a classic anti-hero. I’m sure that was always David Simon’s intention.
Billy Bob Thornton’s character in Fargo, Lorne Malvo. If I was making a movie with the Devil in it…I’d cast Billy Bob as Lorne Malvo. Pure, sociopathic evil…with a hint of whimsy.
Bugs Bunny…after all, we have testimony from one of his closest associates…
I’m sure it was. McNulty’s a very well written character. I just can’t stand him.
Can’t believe I misspelled “roles” twice in the same post. Senility has set in.