Villains can be a vital part of a movie, often relying on the actor to evoke emotions in an audience that stem from fear to create an iconic role. While an audience will root for the hero, a villain is just as intriguing to watch, especially if viewers can't predict their next unnerving move.

From superhero movies to psychological thrillers, actors have proven there's more than one way to portray a villain. But among the most memorable are those that were so well acted that it's hard to imagine another actor taking up the role, no matter how skilled they may be.

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10 Saruman (The Lord of the Rings)

Close up of Saruman in The Lord Of The Rings

The creatives behind The Lord of the Rings didn't neglect any element of the franchise. They produced breathtaking scenery, an exemplary script, and a truly transportive movie soundtrack. The cast embodied their characters seamlessly, and among them was Christopher Lee playing Saruman.

If not done well, the portrayal of fantasy can be so far removed from reality that it becomes disengaging. However, in this case, Lee was a perfect example of an actor that kept the role credible but undeniably wicked. He made his mark not only as an evil wizard but as one of the most iconic villains.

9 Kathy Bates as Annie (Misery)

Annie Wilkes holding a knife in Misery.

Disturbing and unpredictable, Misery had viewers on the edge of their seats. The film hooked viewers from the moment people realized that Annie was not the kind of person anyone wanted to be rescued by. Kathy Bates made the role her own, allowing audiences to witness the transition from being a kind stranger to an evil captor.

Any time the character returned to her house was stomach-churning, with audiences not knowing what her next step would be. Winning an Academy Award for Best Actress, Bates kept the part realistic, and any other actor would be hard-pushed to deliver a performance as menacingly believable as she did.

8 Voldemort (Harry Potter)

Ralph Fiennes grimacing as Lord Voldemort in Harry Potter.

Voldemort is just as important as the titular character himself in Harry Potter. The magical world had its fair share of good and evil, with both sides being defined with equal clarity. Voldemort was the opposite of Harry, made abundantly clear by the actor's skills.

Ralph Fiennes was perfectly cast as Voldemort -- the forefront of the darkness in the movies. Visually, his costume and makeup added to the immediate shock of his presence, but it was Fiennes that brought the character to life as the antithesis of good. Setting the standard for how the role should be played, it's hard to entertain the thought of another actor playing Voldemort.

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7 Richmond Valentine (Kingsman: The Secret Service)

Richmond Valentine talking to Harry in Kingsman: The Secret Service

The Kingsman movies were fun and energetic. The franchise had all the gadgets and secret rooms fans could hope for. As glamorous as the work was made to look, Eggsy (Taron Egerton) came up against unforgettable villains, including Richmond Valentine, played by Samuel L Jackson.

A villain that tried to hoodwink others with a smile on his face gave chase to his enemies, with traits of a mastermind. Jackson elevated the role with quirky characteristics that only he could pull off. He made sure the character would stick in the minds of its audience.

6 Mr. Blonde (Reservoir Dogs)

Mr. Blonde (played by Michael Madsen) as he appears in Reservoir Dogs

As an impressive directorial debut for Quentin Tarantino, Reservoir Dogs set him off into a career of success. The crime film was laced with Tarantino's stylized approach, not least of which involved characters that linger in the minds of viewers.

While Reservoir Dogs was an ensemble piece, Mr. Blonde, played by Michael Madsen, stood out with an unsettling slickness epitomized in his famous torture scene. Madsen's most frightening aspect came with his slow movements, not needing to overdramatize the performance to achieve the desired fear factor. The role required a particular portrayal that Madsen delivered, seemingly with ease.

5 Hans Gruber (Die Hard)

Hans Gruber looking menacing in Die Hard.

The late Alan Rickman was highly skilled in every role he undertook. Whether it was in the romantic comedy Love Actually or as Professor Snape in Harry Potter, Rickman made the characters his own. Before both of those parts, Rickman made a significant impression on fans in Die Hard.

Playing main antagonist Hans Gruber, Rickman commanded every scene he was in. He gave a threatening presence that would stop anyone in their tracks. The actor's eminence was justified with this part alone, which no one else could remake because it would be near impossible to live up to such a performance.

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4 The Wicked Witch of the West (The Wizard of Oz)

The Wicked Witch of the West looks condescendingly at Dorothy in The Wizard of Oz.

After 84 years, The Wizard of Oz is still a well-remembered movie. Dorothy's sweet demeanor and her adorable dog Toto from the movie were perfectly contrasted with a frightful witch, played by Margaret Hamilton.

Hamilton's cackle was everything a witch's laugh should be; grating, troubling, and causative of a sinking feeling that something terrible was going to happen. The film did have versions prior to the 1939 adaptation. However, Hamilton's portrayal of the witch is the one that stands out.

3 May Day (A View to a Kill)

Close up of Grace Jones as May Day in A View To A Kill

James Bond films were inundated with great villains. They each had their own motives and distinctive characteristics that induced terror among audiences and other characters facing them. May Day began as villainous, later turning into a more antiheroic character.

Nonetheless, Grace Jones made the role sharp and powerful. There was no opposition that stood as too much of a contender for May Day to take on. She brought a uniqueness of elegance and strength that set her apart from most Bond villains, owning her role that no one else could step into.

2 Loki (Avengers)

Loki smiling while being chained up

The MCU has gifted fans with a plethora of heroes, villains, and everything in between. Though many of them have reasons as to why they should be recognized as iconic, Loki is a particular villain that captured the attention of viewers. The role is excellently played by Tom Hiddleston.

Hiddleston held his own among the vast cast of heroes and villains. The smug swagger Hiddleston added to his character was almost every bit as villainous as his cruel actions against others. Later, when more vulnerability was required of him, Hiddleston began to layer the character more intricately.

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1 Tommy DeVito (Goodfellas)

Tommy DeVito played by Joe Pesci laughing in Goodfellas.

Gangster movies are a popular theme, especially when Martin Scorsese is the director. Goodfellas depicted the true story of gangster Henry Hill and his life in the mob. Joe Pesci was a core part of the cast, playing Tommy DeVito, one of the most terrifying villains in the movie.

His famous "funny how?" scene created the impression that Henry's life hung in the balance, depending on whether Tommy thought he was being humiliated. Quickly, Tommy snapped out of his disturbing confrontation but proved that no one was safe in his presence. Pesci's chilling performance gave what felt like a true representation of organized crime and a characterization that left the character untouchable for other actors.