Although Kevin Feige has said it’ll be a while before mutants show up in the Marvel Cinematic Universe, since the rights to the X-Men characters reverted back to Marvel in the Disney/Fox merger, the X-Men franchise will eventually get an Avengers-adjacent reboot. All the iconic roles will need to be cast again, having already been cast twice in the Fox series.

RELATED: 5 Directors Who Almost Helmed An X-Men Movie (& 5 Who Should)

In Fox’s X-Men franchise, most of the casting was spot-on. Even the worst X-Men movies featured some of the greatest actors in the world, from James McAvoy to Michael Fassbender to Jennifer Lawrence. But they were rarely the first choices for their roles.

Perfectly Cast: Hugh Jackman As Wolverine

Hugh Jackman in Logan

Hugh Jackman was inducted into the Guinness Book of World Records for the longest on-screen stint as a superhero after playing Wolverine across two decades.

From his introduction as a hotshot young renegade in the original movie to his tragic R-rated swansong in James Mangold’s neo-western gem Logan, Jackman’s Wolverine was one of the most complex, lovable, fascinating comic book heroes on the big screen.

Almost Cast: Russell Crowe

Russell Crowe as Maximus screaming in the arena in Gladiator

Russell Crowe was the original choice to play Wolverine, but he turned down the part as he considered it to be too close to the role he played in Gladiator. Aaron Eckhart, Viggo Mortensen, Edward Norton, and Keanu Reeves all met with the producers to discuss the role.

Dougray Scott was cast but had to drop out due to his commitments to Mission: Impossible II. Crowe then suggested his friend Hugh Jackman to the producers and the rest is history.

Perfectly Cast: Ian McKellen As Magneto

Magneto using his powers in X-Men The Last Stand

Before Heath Ledger played the Joker or Michael B. Jordan played Erik Killmonger, and even before Alfred Molina played Doctor Octopus, Ian McKellen set a high bar for big-screen portrayals of supervillains as Magneto in X-Men and its sequels.

McKellen has a warm personality in real life, but he brought a real sinister edge to Magneto in the X-Men franchise. He also brought a humanity to Magneto that made a compelling case for his side of the mutant rights argument.

Almost Cast: John Hurt

John Hurt in Tinker Tailor Soldier Spy

Before Ian McKellen was cast to play Magneto in X-Men, a few legendary actors of his caliber were considered for the part, including John Hurt, Christopher Lee, and Terence Stamp.

David Hemblen, who had previously voiced Magneto on the fan-favorite cartoon X-Men: The Animated Series, was also considered for the role.

Perfectly Cast: Dafne Keen As Laura

Dafne Keen in Logan

Since Disney acquired 21st Century Fox and the X-Men franchise is about to get a reboot in the MCU, the proposed X-23 spin-off will probably never happen, which would be a real tragedy because the character got one heck of an introduction in Logan.

RELATED: Logan: 10 Ways It's The Best Wolverine Movie (By Far)

Wolverine’s long-lost cloned daughter was given all of her father’s unbridled rage, but with a dash of childhood naivety, in a powerful performance by Dafne Keen.

Almost Cast: Millie Bobby Brown

Millie Bobby Brown in Stranger Things

Millie Bobby Brown did a screen test for the role of Laura in Logan before Dafne Keen was cast. In her audition, she performed the scene in which Laura hits Logan opposite Hugh Jackman.

Interestingly, the scene in which Laura goes into a convenience store and uses the immunity provided by her superpowers to take whatever she wants ended up having presumably unintentional parallels with a similar Eggo-heist scene revolving around Brown’s star-making role Eleven in Netflix’s Stranger Things.

Perfectly Cast: Patrick Stewart As Professor X

Patrick Stewart as Professor X

Patrick Stewart apparently wasn’t content with playing just one sci-fi icon, having starred as Captain Picard on Star Trek: The Next Generation for seven seasons, so he took on the role of Charles Xavier, too.

Stewart is a formidable actor, bringing pathos to every scene, and he also shared terrific chemistry with Ian McKellen, creating a tangible dynamic between their friends-turned-mortal-enemies duo. When Xavier and Magneto share the screen, it has the weight of a meeting of titans because, in many ways, it is.

Almost Cast: Michael Jackson

Michael Jackson

Before Patrick Stewart was cast to play Charles Xavier, Michael Jackson met with Marvel about possibly playing the part. Jackson wasn’t much of an actor, but he would’ve given the movie a lot of star power.

RELATED: X-Men: 10 Characters And The MCU Icons They Should Team Up With

Jackson was such a huge Marvel fan that he once tried to buy Marvel Comics just so he could play Spider-Man in a movie.

Perfectly Cast: Halle Berry As Storm

Storm using her powers in X-Men 2

After considering Mariah Carey, Janet Jackson, and Jada Pinkett Smith for the role of Ororo Munroe, the producers of X-Men finally cast Halle Berry in the role.

Like her co-star Hugh Jackman, Berry nailed both the subtler nuances of her character and the more physical demands of playing a superhero.

Almost Cast: Angela Bassett

Angela Bassett in Black Panther

In the ‘90s, James Cameron was interested in producing a movie called Wolverine and the X-Men and met with Stan Lee and Chris Claremont about securing the film rights to the X-Men.

This project would’ve been directed by Kathryn Bigelow and written by Gary Goldman. Angela Bassett was cast to play Storm, while Bob Hoskins was eyed for the role of Wolverine. Eventually, the movie fell through when Cameron moved on to an R-rated Spider-Man film project that similarly never materialized.

NEXT: MCU: 5 Roles That Were Perfectly Cast (& 5 Actors Who Almost Played Them)