If there's something that's become apparent in recent years, it's that Marvel Studios has a near flawless track record in terms of casting. As we look ahead to the Marvel Cinematic Universe's future, that's apparent from the sort of names who are now signing up to play these heroes and villains.
Unfortunately, mistakes have been made over the years, with some actors - who are great in their own right - failing to do the comic book characters they're playing justice.
We have no doubt that you're going to have some strong opinions about the names who have made the cut in this feature. However, keep reading because there are plenty of compelling arguments here about why these actors didn't manage to live up to what we've seen on the page.
Some will be redeemed, while the time for that has passed for others listed here...
8. Don Cheadle - War Machine
Don Cheadle is a very talented actor, and his work as Col. James "Rhodey" Rhodes certainly hasn't been terrible.
We didn't see enough of Terrence Howard's iteration to do a fair comparison, but his Rhodey had an inherent toughness that Cheadle's does not. It feels like he needs the armor to be a badass, but this is a character who should be formidable without it as well.
We just don't buy into the current version of the character being someone with a tough-as-nails military background, and because of Cheadle, War Machine just feels like Tony Stark's goofy best chum who managed to get his hands on a suit that does all the work.
Hopefully, Marvel Studios will be able to redeem him in the Armor Wars series.
7. James Spader - Ultron
We all love James Spader, and for the version of Ultron Joss Whedon created in Avengers: Age of Ultron, there's simply no faulting his performance.
However, the comic book Ultron isn't the snarky odd bod we saw on screen in 2015. Instead, he's a terrifying big bad who is not to be trifled with, and that's not really something Spader was able to get across in his performance. We're not entirely blaming him for that here, but there was way too much comedy in his work...and he was a tad too human.
Serious mistakes were made with the depiction of Ultron, and while Spader wasn't necessarily miscast (it's possible another actor might have added the required menace), this didn't really work.
We'd love to see a better take on Ultron down the line, but aren't banking on it.
6. Finn Jones - Iron Fist
These Netflix shows were admittedly MCU-adjacent, but this is too big of a character to overlook here.
We're all too aware that many fans would like to see an Asian actor take on the role of Danny Rand, and there's an argument to be made for that. Finn Jones' race wasn't the issue here, however, and this was as simple as the actor being a poor match for a character who is vastly more interesting and formidable on the page.
As you're likely starting to realise, poor writing and creative decision have hampered many of the actors listed here, but Jones simply wasn't good enough to elevate the material.
This hippy Iron Fist who walked around New York City barefoot and struggled to use his powers was just a total disaster, and this actor simply didn't bring the required pathos and depth to Danny to do the hero justice.
5. Jeremy Renner - Hawkeye
Look, Jeremy Renner's work in the MCU has by no means been bad. He's taken a character who started off as a cameo (and became little more than a mind-controlled drone in The Avengers) and given him some depth, but this Hawkeye...well, he's very much an original creation.
Lacking the cockiness and wit of his comic book counterpart, Renner's Clint Barton is a straight man to the more interesting Avengers.
We've never seen this Hawkeye butt heads with Captain America, romance Mockingbird, or unleash the sort of crazy trick arrows that made him such an essential part of the team. That's out of Renner's control, of course, but the actor...well, he's just a little too bland to play Clint.
Again, we're optimistic this might change when Disney+'s Hawkeye rolls around.
4. Christopher Eccleston - Malekith
Christopher Eccelston has talked openly about not enjoying his time in the MCU, but guess what Chris? We didn't enjoy having to watch you butcher the great villain that is Malekith the Accursed!
Admittedly, Jason Aaron hadn't yet reinvented him as a foe of the Mighty Thor's at this stage, but there was still plenty of great material from the comics to pick from. However, by casting Eccleston (who honestly isn't a great actor - sorry, Doctor Who fans!), Marvel Studios set the stage for a generic bad guy who nearly killed the Thor franchise.
We have nothing good to say about this iteration of Malekith, and Eccleston does deserve the lion share of blame.
It felt like he was going through the motions and not even remotely interested in the character he had been tasked to bring to life on screen. We know the material didn't necessarily inspire him, but that's really no excuse.
3. Michael Douglas - Hank Pym
We love Michael Douglas and the version of Hank Pym he plays is perfectly acceptable. However, he isn't really the Hank Pym as Marvel Studios' decision to totally overhaul the character has left him unrecognisable to fans.
No longer a founding member of The Avengers, this Hank also didn't create Ultron, has no mental health problems, and certainly hasn't taken on mantles like Yellowjacket and Giant-Man.
So much history has been wiped away that we're left with a shell of a character.
Douglas does his best with the material he's given - whether it be the deadbeat dad or unlikely mentor - but that doesn't make him the Hank we all know and love (and occasionally hate) from the comics.
2. Aaron Taylor-Johnson - Quicksilver
Another disappointing Avengers: Age of Ultron character, Quicksilver was cut off at the knees before he could ever pick up speed in the MCU.
However, even if he hadn't died, it feels like this Pietro Maximoff never would have reached his full potential becoming the duplicitous, smarmy, and often cocky Quicksilver who has been both a hero and villain. There were elements of that in Johnson's performance, but the actor simply didn't have the right material to work with here.
It says it all that Evan Peters managed to do a better job as Pietro playing a fake version of the character in the limited screentime he had in WandaVision!
Here's hoping Johnson has better luck playing Kraven the Hunter.
1. Scarlett Johansson - Black Widow
We're going to upset a lot of people with this entry, but there's simply no getting around the fact that as great as the MCU's Black Widow is, she simply isn't the same super spy from the comics.
Scarlett Johansson is a great actress, and she's certainly someone who has brought a fair bit of gravitas to this world at times (there's no faulting her final scene in Avengers: Endgame). Despite that, with an American accent, a pretty generic skillset, and a lack of history with characters like Daredevil and Iron Man, Black Widow could just as easily be, say, Mockingbird.
It feels like Marvel Studios is looking for a second chance with the introduction of Florence Pugh as Yelena Belova, a character who appears to be much closer in line to Natasha Romanoff's comic book counterpart.
We'll be sad to say goodbye to Scarlett in some ways, but her Black Widow...well, over the past decade, she simply hasn't done the source material justice.