When it comes to building franchises, Hollywood tries desperately to stay consistent. If the first movie is a hit, studios will try their hardest to keep the same directors and actors on board as long as possible.
But there are instances in which change is necessary. Sometimes for the betterment of a movie, but sometimes they leave viewers scratching their heads.
From "Batman" to The National Lampoon "Vacation" franchise, check out the most notable recastings in movie history.In 1980's "Star Wars: The Empire Strikes Back" we see the Emperor for the first time as he speaks to Darth Vader via holograph. The Emperor was actually played by Elaine Baker, then wife of special makeup effects legend Rick Baker. The voice was done by New Zealand actor Clive Revill.
For the next film in the saga, "Return of the Jedi," George Lucas recast the role with Scottish actor Ian McDiarmid, who not only went on to play the Emperor in the prequels, but was placed into the "Empire" scene when Lucas updated the films in the early 2000s.
Though Anthony Hopkins won an Oscar for his performance as Hannibal Lecter in "The Silence of the Lambs" (and would play the part two more times), he wasn't the first to star as the good doctor.
Brian Cox played the role in the 1986 Michael Mann film "Manhunter." The character name was spelled "Lecktor" and appeared in just one brief scene, but Cox's portrayal is equally chilling.
Jodie Foster also won an Oscar for her work in "The Silence of the Lambs." But when asked to reprise the role of FBI agent Clarice Starling for the long-delayed sequel, "Hannibal," she declined because she reportedly didn't like how Starling was portrayed in the book.
The very capable Julianne Moore was recast in the role, but nothing helped this sequel, which was ripped apart by critics. It has a 39% rating on Rotten Tomatoes.
Wesley Snipes was another actor to turn down a sequel after playing speedster Willie Mays Hayes in the hit comedy "Major League."
Five years later, when the sequel finally came along, Snipes was on to bigger things, so Omar Epps entered the role of Hayes.
The National Lampoon "Vacation" movies used recasting of the Griswold kids as a running joke (the dad, played by Chevy Chase, could never recognize his children). In the first film, "National Lampoon's Vacation," Anthony Michael Hall and Dana Barron play siblings Rusty and Audrey Griswold.
Then in 1985's "European Vacation," Jason Lively and Dana Hill replaced the roles.
Followed by Johnny Galecki and Juliette Lewis in 1989's "Christmas Vacation."
In 1997's "Vegas Vacation," Ethan Embry and Marisol Nichols took on the roles.
The tradition will continue in July in the "Vacation" reboot, in which Ed Helms will play an adult Rusty taking his kids to Walley World.
Sometimes recasting is caused because of a sudden death. That was the case with actor Richard Harris, who played Dumbledore in the first two "Harry Potter" films.
Following Harris' death in 2002, Irish character actor Michael Gambon took over as Dumbledore.
Similarly, Gloria Foster played the Oracle in the first two "Matrix" films.
But when Foster died in 2001 before her scenes for the final film in the series, "The Matrix: Revolutions," were shot, actress Mary Alice was hired. Aware the audience would see the difference, "Matrix" directors the Wachowski brothers acknowledged the Oracle's physical transformation in the film.
But most often, filmmakers make changes without reference and hope the audience will go along for the ride. Like Jennifer, played by Claudia Wells, in the "Back to the Future" films.
In the sequel Wells was replaced by Elisabeth Shue, hot off being the arm candy of Tom Cruise in "Cocktail." Wells reportedly backed out of the franchise to care for her sick mother.
Crispin Glover's exit from the "Back to the Future" franchise was a little more dramatic. Playing the crucial role of George McFly in the original, Glover reportedly demanded a larger salary and script approval for the sequels.
Instead director Robert Zemeckis cleverly used another actor, Jeffrey Weissman, to double as Glover, filming him in wide shots, shooting the back of his head, and even turning him upside down to play the George McFly role.
Money also played a part in why Terrence Howard never returned to the role of James "Rhodey" Rhodes after the first "Iron Man" movie. According to reports, Howard tried to get more money for the sequels, though he says he was offered less than what was originally agreed upon for the sequel.
Don Cheadle took on the role for the rest of the "Iron Man" films and carried it into "The Avengers" franchise.
"The Avengers" franchise also had its share of drama. Many assumed Edward Norton, who played the Hulk in 2008's "The Incredible Hulk," would join the team.
But leading up to production on "The Avengers," Marvel Studios head Kevin Feige said he wanted an actor "who embodies the creativity and collaborative spirit of our other talented cast members" to play Bruce Banner. Cue Mark Ruffalo.
After the second movie in the "Twilight" saga, the film's studio announced that actress Rachelle Lefevre, who played Victoria, would no longer be in the franchise because of previous scheduling commitments.
She was quickly replaced by Bryce Dallas Howard. Lefevre didn't go away quietly, however, saying there was no scheduling conflict on her end and she was "fully committed" to continue.
Alec Baldwin became a movie star after playing Jack Ryan in "The Hunt For Red October." And he wanted to play Ryan again.
But according to Baldwin years later, he was pushed out when the director and the studio learned they could get a very big actor for the sequels. Harrison Ford would go on to play Jack Ryan in the sequels "Patriot Games" and "Clear and Present Danger."
There are the rare times when recasting is done in a civil manner. Robert Rodriguez launched his career by making the ultra-low-budget movie "El Mariachi," starring unknown Mexican actor Carlos Gallardo in the lead.
When Rodriguez had the opportunity to make a bigger-budgeted sequel, "Desperado," Gallardo stepped aside to give the role to Antonio Banderas. Gallardo got a small role in the film.
Things were also cordial during the recasting of the Rachel Dawes character after "Batman Begins," originally played by Katie Holmes.
With the studio interested in Maggie Gyllenhaal to play the role in "The Dark Knight," Holmes obliged so she could instead star in the comedy "Mad Money" alongside Diane Keaton. Gyllenhaal reportedly did reach out to get Holmes' blessing before accepting the role.
But perhaps the most damaging sequel recasting in recent memory was what happened to the "Batman" franchise during the Tim Burton era. For the third film, "Batman Forever," Burton took a producer role and passed the directing reins to Joel Schumacher. With a more lighter feel planned for the movie, Michael Keaton declined to return as the Dark Knight.
Val Kilmer put on the tights, and so began the franchise's downward spiral as the movies became more hokey and completely alienated the core Batman fan base.
Now check out...
THEN & NOW: The cast of 'Jurassic Park' 22 years later >
See Also:The lost 25-minute short film that originally debuted in front of 'Star Wars: Episode V' is finally available to watchChristopher Lee did his incredible lightsaber fight against Yoda in 'Star Wars' when he was 79The first reported 'Batman v Superman' synopsis hints at a new villain