Source @ The CinemAttic
10. Agent Smith – The Matrix (1999), The Matrix Reloaded (2003), The Matrix Revolutions (2003)

“Mr. Aaaanderson.” Hugo Weaving’s calculated drawl made Smith the most evil computer programme since that shitey little paperclip from Word. Smith adds to the damning cinematic evidence that Artificial Intelligence is capable of nothing but pure, nasty evil.
9. The Wicked Witch of the West – The Wizard of Oz (1939)

This hell-ho is often labelled the modern archetype for human wickedness. For the purposes of this post, we shall label her: dagnasty wicked. She’s SO evil she even gave confused monkeys the ability to fly. IT’S NOT NATURAL!
8. Jigsaw – Saw (2004), Saw II (2005), Saw III (2006)

He may have never killed anyone directly, but the things he forces them through are horrifically nasty. He considers himself more of a vigilante than a twisted psychotic; but if you really want people to appreciate life, inserting keys in their eyes and taunting them with a creepy puppet isn’t the nicest way to do it.
7. The Joker – Batman (1989)

Jack Nicholson’s superb take on this insane maniac was a welcome departure from the super-campness of Cesar Romero’s Joker. Sometimes amusing, sometimes terrifying, one thing was certain; he was pure evil.
6. Nurse Ratched – One Flew Over the Cuckoo’s Nest (1975)

The most wicked, horrible bitch ever to grace the big-screen. Feeding off the immortal power of head nurse, she shocks, abuses and humiliates the patients into doing her bidding. And she has McMurphy lobotomised! I’m quivering with rage even just thinking about her.
5. Michael Myers – Halloween (1978), Halloween 2 (1981), Halloween 4 (1988), Halloween 5 (1989)… (sigh)… and all the rest

“I met him, fifteen years ago,” says Dr. Sam Loomis. “I was told there was nothing left. No reason, no conscience, no understanding; even the most rudimentary sense of life or death, good or evil, right or wrong. I met this six-year-old child, with this blank, pale, emotionless face and, the blackest eyes… the *devil’s* eyes! I spent eight years trying to reach him, and then another seven trying to keep him locked up because I realized what was living behind that boy’s eyes was purely and simply… *evil*!” Enough said.
4. The T-1000 – Terminator 2: Judgement Day (1991)

He may be an emotionless machine but he was programmed with evil intent and that makes him evil. And by Lucifer, he had the evil tools and intent for the job. Which made him scarier than the Austrian model. Being chased by the T-1000 would probably be the most opportune time to take up incontinence.
3. Norman Bates – Psycho (1960)

A psychologist’s dream,
Norman is utterly, utterly messed up in the head. Multiple personalities, Oedipus complexes and homicidal tendencies all attribute to a ridiculously warped and evil mind. He may be quite a tragic character, but it doesn’t detract from his nastiness.
2. Hannibal Lecter – Manhunter (1986), Silence of the Lambs (1991), Hannibal (2001), Red Dragon (2002), Hannibal Rising (2007)

“I ate his liver with some fava beans and a nice Chianti.” Cannibalism, murder and a keen nose for wine, Lecter is pure intellect and evil. The only villain who could remain terrifying behind three inches of reinforced glass, he kills for calm and calculated reasons. Utterly terrifying, utterly evil.
1. Darth Vader – Star Wars Episodes III (2005), IV (1977), V (1980), VI (1983)

The most evil villain of them all and the scariest boss in the galaxy. Disagree with most bosses, you might get a pay cut, disagree with Vader and you’ll be getting a fistful of Force down your throat. Vader destroyed entire planets without flinching, wiped out all the Jedis without batting an eyelid and even killed his beloved wife (through the medium of heartbreak). Forget the good that Luke sensed within him, that was merely the remnants of that pussy Anakin. Darth Vader was pure, 100% dagnasty evil. Even his breathing was evil.