Janet Hubert left the show amid a contract dispute. Daphne Maxwell Reid replaced her as Aunt Vivian.
Ed Skrein played Dany's boy toy Daario for barely a season before his role was recast. Michiel Huisman assumed the role starting in season four in 2014.
Despite shooting three to five weeks of footage for the movie, Eric Stoltz was still replaced by Michael J. Fox.
In June 2017, Ron Howard was chosen to replace Phil Lord and Chris Miller as the director of the Han Solo film after they were fired due to "creative differences."
Though she's been with the show since it first debuted in 2011, Aimee Richardson learned Nell Tiger Free would be taking over the role of Princess Myrcella Baratheon in season five. Richardson wasn't too distraught though, posting a hilarious Vine video in which she holds a sign reading "princess for hire."
After Charlie Hunnam dropped out of the steamy production, the search for the next Christian Grey ended with Jamie Dornan, the hot Irish star of The Fall and Once Upon a Time. And judging from the first trailer for the steamy flick, Dornan fit the domineering role just fine.
Tobey Maguire was reportedly "too famous" to play the Writer character in Ang Lee's Oscar-winning film and was replaced by lesser-known Rafe Spall.
The Girl With The Dragon Tattoo star Rooney Mara said she couldn't star in the Oscar favorite because of scheduling conflicts. Lucky for Jessica Chastain, the role became all hers and even made her a Golden Globe winner.
After getting tied up in shooting Mission: Impossible 2, Dougray Scott had to pass on the role. Instead, Aussie actor Hugh Jackman stepped in as one sexy Wolverine.
Even though production was halted to allow Maura Tierney time for her breast-cancer treatments, the show eventually had to recast the role of Sarah Braverman to with onetime Gilmore Girl Lauren Graham.
Shortly after Shia LaBeouf dropped out of the Broadway play due to "creative differences," the production signed The Messenger star Ben Foster to replace him. The role would mark Foster's Broadway debut.
Ryan Gosling revealed that he was fired from Peter Jackson's 2009 movie because his 60-pound weight gain didn't sit well with producers. Try not to be too upset. Mark Wahlberg replaced him and he's just as easy on the eyes.
Cory and Eric's younger sister, Morgan, wasn't the same girl during the entire series. Lily Nicksay did the honors from 1993 to 1995 while Lindsay Ridgeway took over in 1996.
Marvel bosses replaced Terrence Howard with Don Cheadle after a salary dispute. Is Howard still bitter? "Marvel made a choice, and it was a very, very bad choice," the actor said.
In the show's pilot, former Saturday Night Live castmember Rachel Dratch played the role of Jenna Maroney. In the end, Jane Krakowski landed the hilarious gig with Dratch still making several appearances.
After signing onto Magnum P.I., Tom Selleck chose to turn down the movie role, making way for Harrison Ford to play the man in the fedora.
In order to attend Vassar College, Lecy Goranson had to leave the show after five years. Sarah Chalke stepped in, but fans couldn't help but notice Becky's ever-changing face.
While filming the Lord of the Rings trilogy, director Peter Jackson worried Stuart Townsend was too young to play the hero. Luckily, Viggo Mortensen was available (and older) for the role.
Suffering from a bad back condition, Dick York caused a number of shooting delays and rewrites. After leaving the show, Dick Sargent or "The Other Darrin" stepped in for the next three seasons.
After playing Rachel Dawes in Batman Begins, Katie Holmes decided to drop out for the film's next Batman installment. Maggie Gyllenhaal ended up costarring alongside Christian Bale.
Two weeks before filming was set to begin, Sylvester Stallone left the project and Eddie Murphy stepped in. After massive rewrites were made, the action comedy film was finally made. Producer Jerry Bruckheimer later claimed the role was also offered to Mickey Rourke.
When Hollywood bought the rights to the story, author Truman Capote wanted Marilyn Monre to play Holly Golightly. In the end, Audrey Hepburn got the iconic role of a young, beautiful New York socialite.
Almost two months before the film's release, Al Pacino abruptly pulled out of the animated sequel citing "creative differences" with Universal Pictures. Benjamin Bratt quickly filled the void left by the Oscar-winning actor.
Originally, Laura Marano played adorable 10-year-old Gracie Carr on the Fox comedy. After producers decided to "go in a different direction," My Name Is Earl actress Lily Jackson stepped in.
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