Will Ferrell
Elf was such a hit that fans demanded a sequel. A script for a sequel actually got written and Will Ferrell was offered $29 million to reprise the role, but he said no. He thought the plot was a cheap rehashing of the original film. “I would have had to promote the movie from an honest place, which would’ve been, like, ‘Oh no, it’s not good. I just couldn’t turn down that much money.’ And I thought, ‘Can I actually say those words? I don’t think I can, so I guess I can’t do the movie,'” Ferrell told THR.
Marlon Brando
Marlon Brando earned an Academy Award for his role of Don Vito Corleone in the 1972 film The Godfather. Don Vito dies from a heart attack in the first film, but the second film was supposed to feature "new" flashbacks. Brando signed on to do the flashbacks but he never showed up for filming. Instead, they hired Robert De Niro to fill the part and the rest is history.