The 11 Unlikeliest Actors Ever Cast in Superhero Movies

The greatest criminal mind of our time might very well be ... Joaquin Phoenix?

Big buzz on "Batman vs. Superman" continues as Variety reports that the Oscar-nominated star of "Walk the Line" is a wanted man ... for the role of the main antagonist in the upcoming superhero mashup/"Man of Steel" sequel, which sources say is probably Lex Luthor.

Phoenix has been making quite a comeback since all of that "I'm Still Here" nonsense, particularly with his intense (and Oscar-nominated) performance in Paul Thomas Anderson's "The Master" (2012). He's currently receiving raves for his romantic turn in Spike Jonze's "Her," and Warner Bros. seems to be keen to work with him on its biggest property.

[Related: Batman and Superman Get Their Wonder Woman]

That's not all. On the other side of the street, it would appear the gang at Marvel Films finally has their "Ant-Man" ... in the form of "Anchorman 2" funnyman Paul Rudd, according to The Wrap.

The head-scratcher here isn't that these two actors wouldn't be great in their respective roles — they most definitely would. It's just that both Joaquin Phoenix and Paul Rudd don't scream "superhero movie actors" at first glance. Phoenix is a 'serious thespian' who hasn't really starred in a major tentpole since his villainous turn in "Gladiator" (2000), and Rudd is ... well, he's the guy who almost swallowed his own fist while he was having a hallucinogenic-induced Las Vegas freak-out in "Knocked Up" (2007).

[Related: Ant-Man, Dr. Strange Lead the Charge in Marvel's Next Wave of Movies]

These two are in interesting company, though, as there's actually been lots of 'unlikely casting' in this genre from over the years. Here are 11 actors whom we never thought we'd see in a superhero movie, either.

1. Marlon Brando in "Superman" (1978)

The notorious Method actor and star of such serious dramas as "On the Waterfront" (1954) and "The Godfather" (1972) as ... Superman's Kryptonian father? Director Richard Donner demanded 'verisimilitude' in what's still the best-ever "Superman" film, and he helped achieve it by attracting A-list actors like Brando and Gene Hackman to what was previously perceived as simply a "funny papers movie."

2. Paul Giamatti in "The Amazing Spider-Man 2" (2014)

Hollywood's go-to sad sack and star of such melancholy character dramas as "Sideways" (2004) as ... one of Spider-Man's most physically imposing and toughest foes? Giamatti's casting as the Rhino in next summer's "Spider-Man" sequel was one of the biggest surprises Sony Pictures has ever pulled, though it later made a little more sense upon the revelation that the character has been reimagined as a guy in a mech suit. Dammit, we kind of wanted to see Giamatti in the traditional Rhino get-up ...

3. Kelsey Grammer in "X-Men: The Last Stand" (2006)

Frasier from "Cheers" was the perfect choice for the role of Dr. Hank McCoy, the intelligent, eloquent, and hopelessly blue fur-covered mutant in "X-Men: The Last Stand" (he's also our No. 1 choice for the role of Thurston Howell III in the just-announced "Gilligan's Island" movie). Perfect, but completely unexpected.

4. Katie Holmes in "Batman Begins" (2005)

Joey from "Dawson's Creek" as Bruce Wayne's childhood friend and would-be ladylove? While we don't understand a lot of the criticism of Katie Holmes's performance in Christopher Nolan's flagship Batman reboot (really, she was fine in the role), we are a little surprised that she got the part of the love interest in one of Warner Bros.' biggest tentpoles in the first place.

5. Anthony Hopkins in "Thor" (2011)

That's 'Sir' Anthony Hopkins to you. And we never thought a 'Sir' would ever play the role of Odin, Ruler of Asgard, father of Thor, the God of Thunder. Maybe Hopkins thought he was following in the footsteps of 'Sir' Laurence Olivier's turn as Zeus in "Clash of the Titans" (1981).

6. Gwyneth Paltrow in "Iron Man" (2008)

Before her (completely awesome) turn as Pepper Potts, the former Darling of Miramax always seemed so serious, hardly ever letting her hair down as she traversed what seemed like a very meticulously planned Career Path. She first revealed that she might be interested in this whole 'comic book movie' thing — or at least the style of it — in 2004 when she appeared as the similarly-named Polly Perkins in "Sky Captain and the World of Tomorrow." Now she's Tony Stark's girl, and we couldn't be happier.

7. Ron Perlman in "Hellboy" (2004)

True, he was the first choice for the role from the star for both director Guillermo del Toro and "Hellboy" comics creator Mike Mignola. We just never thought that Hollywood would green-light a $66 million tentpole film that stars Ron Perlman.

[Related: Role Recall - Ron Perlman Reminisces on 'Hellboy,' Brando and More]

8. Chris Pratt in "Guardians of the Galaxy" (2014)

Andy from "Parks and Recreation" as a guy named Star-Lord, leader of an intergalactic team of superheroes? It actually makes a little more sense when you consider the fact that his colleagues include a gun-crazy raccoon and a giant walking, talking tree.

9. Robert Redford in "Captain America: The Winter Soldier" (2014)

Whoever it was at Marvel Films who convinced the Sundance Kid to star as a high-ranking S.H.I.E.L.D. exec in the new "Captain America" movie deserves a raise, a promotion and maybe even a medal. Redford's what we're looking forward to the most in the upcoming sequel, and that's saying a lot, 'cause Scarlett Johansson's in it, too.

10. Seth Rogen in "The Green Hornet" (2011)

Yeah, this really didn't work out. Rogen did, though — he shed 30 pounds to play the masked avenger with the sweetest ride this side of the Batmobile.

11. Mickey Rourke in "Iron Man 2" (2010)

What do you do after an Oscar-nominated career comeback? Play the bad guy in a superhero movie, of course. Whatever good will notorious Hollywood bad boy managed to score with his excellent turn in "The Wrestler" (2008) pretty much dissolved after his ill-advised turn as Ivan Vanko in "Iron Man 2," though it's not completely his fault — it's not like the character was, you know, written well or anything.

[Related: Why Brad Pitt Could Play Alfred in 'Batman vs. Superman']