"Gravity" may be a huge success at the box office, but director Alfonso Cuarón didn't initially envision Sandra Bullock and George Clooney in the film's lead roles.
Instead, Cuarón was hoping for Angelina Jolie and Robert Downey Jr. When Jolie passed, Natalie Portman was offered the role. We all know who ended up getting the gigs.
But casting swaps in Hollywood are nothing new. In fact, many of this year's biggest movies initially had different actors attached.
See who could have starred in your favorite films, according to Vulture:
"Oz, the Great and Powerful":
Robert Downey Jr. was initially signed on but dropped out over creative differences with director Sam Raimi.
Raimi then tried to cast Johnny Depp, but he was committed to "The Lone Ranger."
James Franco eventually got the role as the wizard, and the actor was able to command a $7 million paycheck for filling-in last-minute.
"Man of Steel":
According to director Zack Snyder, the "Superman" role came down to "True Blood" star Joe Manganiello and eventual winner Henry Cavill.
"Iron Man 3":
Jessica Chastain was offered the role of scientist Maya Hansen, but when she dropped out of talks in order to honor her commitment to the indie drama "The Disappearance of Eleanor Rigby," actress Rebecca Hall filled the role.
Jessica Biel reportedly couldn't reach a deal to play villainess, Viper, so was replaced by a virtually unknown Russian actress named Svetlana Khodchenkova.
"Star Trek Into Darkness":
Director J.J. Abrams initially wanted Benicio Del Toro to play character "Khan," but the actor proved too expensive. Actors Edgar Ramirez and Jordi Molla auditioned for the role, but it ultimately went to Benedict Cumberbatch.
"The Fifth Estate":
Benedict Cumberbatch wasn't director Bill Condon's top pick to play Julian Assange in the upcoming WikiLeaks movie. Condon first hoped Jeremy Renner would take the role.
Director Bryan Singer first cast Mark Wahlberg and Christian Bale in the lead roles, but the package quickly fell apart and Hugh Jackman and Jake Gyllenhaal stepped in.
Director Lee Daniels had Hugh Jackman lined up to play John F. Kennedy, with Mila Kunis as his Jackie. After both actors fell out, the director went after Matthew McConaughey and Minka Kelly to replace them, but McConaughey dropped out to film "Dallas Buyers Club." Thanks to a chance encounter running into each other on the street, Daniels cast James Marsden in the role just a week and a half before the JFK scenes needed to be shot.
"This Is the End":
“Two years before we brought [the script] to anybody else, we brought it to Daniel Radcliffe and he rejected it because it was shitty, it wasn’t good enough,” co-director Evan Goldberg explained to Buzzfeed. After editing the script, James Franco, Seth Rogen, Jonah Hill, Emma Watson, Rihanna, and many others signed on.
Actress Samantha Morton filmed Spike Jonze's "Her" as the Siri-like voice that Joaquin Phoenix falls in love with, but after the film wrapped, Jonze subbed in Scarlett Johansson's smoky voice instead.
"The Secret Life of Walter Mitty":
Over the last decade, Jim Carrey, Will Ferrell, Mike Myers, and Owen Wilson were among the actors who expressed interest in the lead role of the upcoming indie film. But after Sacha Baron Cohen exited the project in 2010, Ben Stiller came onboard to direct and star, and the project finally came together.
To see other casting decisions that didn't see the light of day, read more on Vulture here >
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