When an actor gives an authentic, believable performance, the results can be spectacular. But sometimes a star just doesn't fit into a role no matter how much Hollywood tries to shoehorn them into the part of, say, young Anakin Skywalker. That doesn't stop them from trying, however.

The worst examples of miscasting are a master class in bad acting choices, cheap accents and cringe-inducing line deliveries. Whatever the reason, there are plenty of terribly miscast roles throughout movie history. Here are 10 of the best. Er, worst. You get what we mean.

  • 1

    Hayden Christensen as Anakin Skywalker


    Forget the stilted dialogue, the insipid love story that dominates the second movie or Jar Jar Binks and let's talk about the real problem with the 'Star Wars' prequels -- Hayden Christensen. His turn as Anakin Skywalker comes off as bratty, petulant and completely lacking in menace. Thanks a lot, pal. You just force-choked our childhood.

  • 2

    Keanu Reeves as John Constantine

    Warner Bros.

    In comics, occult investigator John Constantine is portrayed as a world-weary Brit with a wry sense of humor and occasionally questionable motives. (His appearance is based on The Police-era Sting.) But Keanu Reeves, who played him in a 2005 movie adaptation, just comes off as vacant and dazed. Also, not British. One critic described Reeves as possessing "Zen blankness," but we think that gives his inherent blankness way too much credit.

  • 3

    John Wayne as Genghis Khan

    When it comes to actors who epitomize cowboys and the Wild West, no one's more iconic than John Wayne. That's what makes his portrayal of Genghis Khan in Howard Hughes' 1956 film 'The Conqueror' all the more embarrassing.

    Not only does Wayne sport makeup to make his eyes seem slanted and a ridiculous Fu Manchu-style mustache, he also tries to wrap his drawl around dialogue like, "She is woman, Jamuga, much woman. Should her perfidy be less than that of other women?" Yep, it's as offensive as it sounds.

  • 4

    Mickey Rooney as Mr. Yunioshi


    Mickey Rooney as I.Y. Yunioshi in 'Breakfast at Tiffany's' isn't just an example of spectacular miscasting -- it's also one of the most offensive characters in movie history. Rooney's portrayal of an Asian landlord is a full-on caricature complete with buck teeth and cringe-inducing accent.

    According to Rooney, he exaggerated the character at the behest of director Blake Edwards. But if he'd known Yunioshi would offend people, he never would have done it in the first place. Well, unfortunately his performance has been captured on film for future generations to cringe over.

  • 5

    Colin Farrell as Alexander the Great

    Warner Bros

    As a historical figure, Alexander the Great was a warrior of epic proportions who was tutored by Aristotle and built one of the largest empires in the ancient world by the time he was 30. But we can't imagine Colin Farrell, who played him in 2004's 'Alexander,' doing much more than getting into a drunken bar brawl. And don't even get us started on that blonde mullet thing on top of his head. Oliver Stone, we demand an apology.

  • 6

    Sofia Coppola as Mary Corleone

    Sofia Coppola may have a famous father in the movie biz, but that's no guarantee that she can act. In fact, her performance in 'The Godfather: Part III' is so wooden and utterly lifeless, it helped to kill one of the greatest movie franchises of all time. She even fails to emote in her death scene. Let's put it this way -- it's a good thing Coppola ultimately decided to follow in her dad's footsteps and work behind the camera.

  • 7

    George Clooney as Batman

    Warner Bros.

    Of all the actors who've played Batman over the years, George Clooney is one of the most perplexing. (You get a free pass, Val Kilmer, but just barely.) His performance in 1997's 'Batman & Robin' effectively killed the franchise until Christopher Nolan came along in 2005 with 'Batman Begins.' (Clooney himself even admitted that Joel Schumacher's brightly-colored nipple-fest was a "difficult movie to be good in.") Audiences ultimately forgave George, but it definitely took a while.

  • 8

    Keanu Reeves as Don John

    Look, we like Keanu Reeves as Ted from the 'Bill and Ted' movies and Neo in 'The Matrix', but he should never, ever attempt Shakespeare. When Kenneth Branagh's 'Much Ado About Nothing' was released in 1993, critics generally gave it high marks except for Reeve's performance as Don John, evil half brother to Don Pedro. Simply put, seeing Reeves struggle with the immortal Bard's iambic pentameter is just painful.

  • 9

    Denise Richards as Dr. Christmas Jones


    In 1999's 'The World is Not Enough," Denise Richards has the requisite pouty good looks and belly-baring sex appeal of a Bond girl. But the filmmakers unnecessarily complicated the role by making Dr. Christmas Jones a nuclear physicist. Of course beautiful women can also be intellectual -- we just don't believe Richards has the acting chops to pull off smart and sexy.

  • 10

    Vince Vaughn as Norman Bates


    No matter how hard we try, we just can't picture Vince Vaughn as serial killer Norman Bates. Evidently, audiences couldn't either and made Gus Van Sant's 1998 shot-for-shot remake of 'Psycho' a commercial failure.

    At the time, Vaughn said he was afraid the movie would cause him to be typecast as a murderer. Turns out, he had no reason to worry.