Joel Grey was cast as a Korean martial arts instructor in this film, but there was one obvious problem with that — Joey Grey isn’t Korean. He’s American. The man had to go through four and a half hours of makeup every day to look like an elderly Korean man.
The producer Larry Spiegel assumed they would be able to find an actual Korean who could do the work, but they ended up having a lot of trouble and cast Grey instead. Even at the time, the casting was highly controversial.
Nicolas Cage as Captain Antonio Corelli in Captain Corelli's Mandolin
The real shame of this casting choice was "Captain Corelli's Mandolin" could have been a stellar film if not for choosing Nic Cage as the title character.
Nic Cage has done a lot of good for the movie world and has been in a lot of movies. This one could have been pretty good, but Cage had to be a Greek army captain and a romantic lover, and even on his best days, he can barely get one of those two. So what happened? Well, the central romance strained credulity. That's what the critics said.
Justin Chadwick as Goku in Dragon Ball Z
Taking a manga or anime and turning it into a live-action movie is a tough sell, even for most fans. "Dragon Ball Z," which has guys flying around and shooting laser blasts at each other, is one of the most famous products from Japan ever, and it produced an awful live-action movie.
Justin Chadwick tried (not very successfully) to be the somewhat dimwitted-yet-well-meaning Son Goku, who repeatedly saves the planet from stronger and stronger challenges.
Jared Leto as Morbius in Morbius
Yeah, there are a lot of terrible things about this movie. The only good thing that came out of it was the memes, and even those are fading. Jared Leto thinks he's a great method actor, but as "Suicide Squad" proved, that doesn't mean he is one.
The big issue might be that Leto cares too much – he was using crutches to get around while filming part of Morbius, and thus he needed help going to the bathroom. On the other hand, it might just be that the Leto experiment needs to end.
Maria Bello as Evelyn O'Connell in The Mummy: Tomb of the Dragon Emperor
While Rachel Weisz was able to pull it off in the first two Mummy films, the third saw her replaced by Maria Bello, who seemed to lack the charm that made the chemistry between the two main characters so realistic.
Replacing an actor or actress with someone else is fairly standard practice, but it might have been better to write the character out entirely this time. Instead, have poor Evelyn fall victim to a curse, and introduce a new leading lady to break Rick out of his funk.