The Marvel Cinematic Universe has been around for almost a decade and keeps on growing every year. Their movies and TV shows have been met with critical acclaim and financial success, with very few exceptions. Marvel is also known for casting incredible actors who deliver amazing performances and make awesome movies even more awesome. However, not every casting decision the mighty MCU made has led them to the success they were most certainly aiming for. With so many movies and TV shows, a few mistakes here and there were bound to happen.

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The MCU has certainly amassed an impressive cast of actors both on the small screen and on the big screen. With stars such as Robert Downey Jr., Sigourney Weaver, Samuel L. Jackson and so many more the MCU movies and TV series are jam-packed with A-listers. However, big names do not always guarantee amazing performances. In the end, we're all only human and even the best of us can have a bad day every once in a while. A number of MCU actors, for one reason or another, just couldn't do their character justice despite their efforts. So, keep scrolling and find out which 15 terrible MCU performances ruined great Marvel characters.

15 EDWARD NORTON

Edward Norton Bruce Banner Hulk

Before Mark Ruffalo took on the mantle of the Hulk in Marvel’s The Avengers, the part belonged to Edward Norton. But there is a reason why The Incredible Hulk is Marvel’s most forgettable movie. While it may not have been a complete disaster, the performances across the board weren’t all that great.

Norton delivered an uneven performance, mostly due to "creative" differences between the studio and the actor. Allegedly, Norton wanted to play Bruce Banner as a very serious and brooding character, while Marvel wanted a more fun Hulk in tone with the MCU, which resulted in a complete mess. Not only does Norton’s Hulk seem to be out of place in the MCU, he seems out of place even in his own movie. Luckily, Norton stepped out and the role went to Ruffalo, who’s doing a much better job.

14 ELIZABETH OLSEN

Elizabeth Olsen Scarlet Witch

Elizabeth Olsen’s portrayal of Scarlet Witch is not terrible by any measure; however, it doesn’t stand out among the best ones either. While Olsen’s performance in Captain America: Civil War was solid, Avengers: Age of Ultron is an entirely different beast. Our problem is not with Olsen’s acting in general, but rather with her accent.

Obviously, the actress was attempting an Eastern European accent in line with her Sokovian origin, but it came off very wrong. Yes, Sokovia is a made-up country and we can't know for certain what their accent sounds like, but Olsen’s accent was kind of an overkill. Plus, it tends to come and go frequently, which gets annoying pretty fast. Perhaps that is why they decided to phase it out in her second movie. Which really did turn out for the best, since Olsen delivered a much better performance in Civil War.

13 NATALIE PORTMAN

Natalie Portman Jane Foster

Natalie Portman is far from being a bad actress. This Academy Award winner has done tones of movies in which she delivered absolutely stunning performances. However, her run in the MCU will not be cited among her best work. While Portman was pretty solid in the first Thor movie, her performance in Thor: The Dark World left a lot to be desired.

Portman is a very talented actress and it’s safe to say her talents were completely wasted in the MCU. Especially since the second Thor movie reduced Portman’s character to a mere plot device, not that she had a lot to do in the first one either. So perhaps Portman’s performance felt absent and weak due to a mix of poor writing and the actress’s frustration at the writing.

12 JEREMY RENNER

Jeremy Renner Hawkeye

Hawkeye being undervalued in the MCU has become something of a running joke. Despite the fact that Jeremy Renner’s Hawkeye has been part of the MCU since the first Thor movie, he still has considerably less screen time than his Avengers teammates. Which is why it pains us to have to criticize Renner’s performance as we truly believe he could do better with better writing and more screen time.

But with things being the way they are, Renner’s Hawkeye is one of the biggest disappointments of the MCU. Instead of playing the character as a cocky archer, Renner’s portrayal of Clint Burton can best be described as a flat goody two-shoes who could easily give the Cap a run for his money. The worst part is, at this point there’s pretty much nothing Marvel can do to fix the mess they so carefully created.

11 GWYNETH PALTROW

Gwyneth Paltrow Pepper Potts

The problem most of us have with Gwyneth Paltrow comes down to her personality rather than her acting capabilities. Over the years, Paltrow has tried her dimmest to annoy pretty much everyone, especially with her pretentious lifestyle website Goop. But let’s try and put a pin in that for a moment and take a look solely at her performance in Iron Man.

Here’s the thing, Paltrow is not a bad actress per se and she’s had some pretty stellar performances. However, her portrayal of Pepper Potts in the MCU is fairly inconsistent. Most of the time Paltrow plays the character without any distinguishable personality. She lacks the moxie and individualism perfectly captured by another famous on-screen assistant, Sarah Rafferty’s Donna Paulsen of Suits. Unfortunately, in most of Paltrow's appearances, she failed to endow Potts with any personality and bravado.

10 TIM ROTH

Tim Roth Emil Blonsky

If you're a fan of good old procedural TV shows with a twist then you must recognize Tim Roth from Fox's awesome, but short-lived, Lie to Me. Roth was the perfect fit to portray the genius body language scientist Dr. Cal Lightman and delivered a very strong performance over the course of three seasons. However, Roth was a complete miscast when it comes to his role in The Incredible Hulk.

In one of Marvel's first movies, Roth was cast to play Emil Blonsky, a Royal Marines Captain who gets injected with the Super Soldier Serum and receives a blood transfusion from Bruce Banner, which transforms him into the Abomination. Roth failed to capture the essence of the battle-hardened veteran and his Emil Blonsky quickly became a stereotypical raging Englishman.

9 LEE PACE

Lee Pace Ronan The Accuser

Marvel’s brave move to give a weird bunch of misfits their own movie turned into a huge success. James Gunn’s Guardians of the Galaxy was met with wide critical acclaim and earned tones of money at the box office. The performances of the main cast received mostly positive reviews, however, Lee Pace kind of dropped the ball as the movie’s big bad, Ronan The Accuser.

Pace’s Ronan came off as an irritable tantrum-throwing child, instead of a notorious destroyer of worlds. The actor’s hammy performance was painful to watch and at times incredibly cringey. His melodramatic acting, which reduced the character to a useless, shallow and dull angry blue man, was too much even for an over-the-top movie such as Guardians of the Galaxy.

8 GUY PEARCE

Guy Pearce The Mandarin

Iron Man 3 was a solid movie, albeit a bit rough around the edges. Robert Downey Jr. was as charismatic as always and the action sequences were quite impressive, however, the movie’s villain was kind of a letdown. The whole mix-up about who’s who didn’t quite carry enough punch for a convincing reveal. While this is mostly due to poor writing, Guy Pearce’s performance didn’t help either.

While Pearce did do justice to Aldrich Killian and was rather believable as a brilliant criminal mastermind, he kind of lost all credibility after the reveal that he was indeed the "true" Mandarin. It felt as if the actor himself had no idea what role he was playing till the very end and was as unpleasantly surprised as the audience.

7 SCARLETT JOHANSSON (IRON MAN 2)

Scarlett Johansson Black Widow

Hold your fire, we’re not saying that Scar-Jo is a horrible actress nor that she’s still terrible in her role. In fact, we absolutely love her as Black Widow. The problem we have with Scarlett Johansson's Black Widow is based solely on her performance in Iron Man 2.

Scar-Jo’s MCU debut left us wondering whether Marvel was right to cast her as the femme fatale. Given that she is playing a superspy, Johansson is required to maintain an aura of unreadability, yet Johansson's Black Widow seemed too bland in Iron Man 2. Gradually, she found her footing and in Captain America: The Winter Soldier she pretty much stole the show. Over time, Scar-Jo managed to make the character her own and now we can’t imagine anyone else as Black Widow.

6 LIV TYLER

Liv Tyler Betty Ross

At times it seems as if Marvel chose some of its female leads entirely on the basis of their appearance. Point in question, Liv Tyler. In case you completely forgot about her, which wouldn’t be surprising, Tyler played Betty Ross in The Incredible Hulk. Known for portraying whiny eye-candy characters, Tyler played Betty Ross the only way she knew how.

Tyler’s flimsy, breathy and on-the-edge-of-tears take on Betty Ross was met with disdain. The actress’s bland performance completely missed the mark and turned a beloved comic book character into an unbearable mess. On top of that, Tyler and her co-star Edward Norton had the complete opposite of chemistry. Though, they share the blame for this one because Norton’s portrayal of Bruce Banner was also very poor.

5 MICKEY ROURKE

Mickey Rourke Whiplash

Iron Man 2 came in hot but ended up being one of Marvel’s most disappointing movies to date. Ruined by a shoddy script, questionable casting decisions and less than stellar performances, Iron Man 2 was not the sequel we were hoping for. One of the worst parts about the movie was its villain Ivan Vanko, aka Whiplash played by Mickey Rourke.

Watching the movie makes us wonder if Rourke ever did any research on the character and preparation for the role. His lazy performance made the character seem like a stereotypical hungover Russian with a thick accent and nothing to offer but sheer brutality. Rourke seems to be bored out of his mind and eager to go home, but considering how mind-numbing this movie was who can blame him.

4 TERRENCE HOWARD

Terrence Howard James Rhodes

Remember that time when Rhodey was played by the Empire star Terrence Howard? From this point in time, it  almost seems like a bad dream, but it really did happen. Howard delivered a very weak performance and completely missed the mark with his overly serious and at the same time dismal take on Tony Stark’s best bud, James Rhodes.

Howard portrayed Rhodey with such lack of authority and command, making it impossible for the audience to even imagine that such a straight-arrow, dull and unassertive character could ever become War Machine. Luckily, by the time Iron Man 2 came out Howard was replaced by Don Cheadle, who’s doing an incomparably better job. Cheadle knows how to bring both fun and gravitas to the character and fits with the tone of the MCU.

3 AARON TAYLOR-JOHNSON

Aaron Taylor-Johnson Quicksilver

Avengers: Age of Ultron is a beautiful mess we can't help but love. While the movie did have some pretty cool action sequences, brought a bunch of characters together and had freaking James Spader playing the villain, it failed to deliver as far as character development and story are concerned. A common target of criticism is Aaron Taylor-Johnson’s take on Quicksilver.

Simply put, he was plain boring. Johnson’s portrayal of Quicksilver was so flat that his premature death failed to deliver the emotional punch it was supposed to have. When Loki killed Agent Coulson in The Avengers the audience wept in disbelief, yet when Quicksilver gave his life protecting Hawkeye and a Sokovian child there was no emotional impact. Johnson never gave us a real character we can connect with and care for and in the end, we didn’t.

2 ANSON MOUNT

Anson Mount Black Bolt

OK, we need to talk about the Inhumans. With only two months since its release, Inhumans is already the most talked about and over-analyzed Marvel movie or TV series to date. The messy and pricey IMAX creation left everyone wondering what the hell happened. Among many other issues, the show was victim to very poor acting, especially on part of Anson Mount.

Mount was cast in the role of Black Bolt, whose voice creates destructive sonic blasts, so he spends most of the time mute. And therein lies the problem. Apparently, Mount somehow mistook stoic and confused for mute. Unable to faithfully render emotions through facial expressions alone, Mount ends up looking constantly angry and constipated. Nothing about his performance made us understand the character better.

1 FINN JONES

Finn Jones Danny Rand Iron Fist

Finn Jones’ casting as Danny Rand in Marvel’s Iron Fist was perhaps MCU’s most controversial casting decision. The fans called for Marvel to cast an Asian actor, but the part went to Finn Jones. And while Idris Elba’s portrayal of Heimdall redeemed this controversial casting decision, sadly the same cannot be said for Jones’ performance in Iron Fist.

Jones’ delivered a very poor performance and Danny Rand ended up feeling like a typical spoiled rich white kid, among the likes of pre-shipwreck Oliver Queen. Jones failed to capture all three aspects of Danny Rand - the lost naïve boy, the brilliant businessman, and the kung-fu master. The realization that a character who’s supposed to be the immortal Iron Fist doesn’t come off as a threat ever is both laughable and shameful.

Which MCU actor do you think delivered the worst performance? Let us know in the comments!