We're all highly pleased nowadays that Harrison Ford stepped in to play Indiana Jones when Tom Selleck couldn't, but let's take a look at the opposite end of the spectrum: movies where the first choice actors found themselves unable to participate (or refused), though their replacements failed to capture the magic that the original picks would have presumably conjured up had they been cast.
Before we start, it'd be good to mention some of the actors who didn't make it onto the list: Sylvester Stallone as Axel Foley in Beverly Hills Cop (yes, you read that right), Arnold Schwarzenegger as John McClane in Die Hard (uh-huh) and Michael J. Fox as Bruce Wayne in 1989's Batman (yes, really). Presumably there would have to have been some lifts in his boots or something.
Anyway, on to the real list, starting with...
10. Christopher Walken As Han Solo - Star Wars
Now it probably wasn't a good idea to start off this list by suggesting a recast of such a beloved character, but here we are. As hard as it is to believe, Harrison Ford wasn't George Lucas' first choice to play noted space bandit Han Solo in his infamous sci-fi fantasy adventure. Originally, Lucas had little-known actor/dancer/all around badass Christopher Walken in mind for the part.
When you think about it, Walken is kind of perfect for the role as it appeared in the script. Han is a scheming, manipulative little so-and-so at times, and obviously someone like Walken would be able to pull of that kind of performance off with his trademark intensity and method acting. We're not saying Harrison Ford is terrible in the role (he's great actually), but the version of Han we know now is completely different to the one in the original script - it was only due to Ford's handy-work that Han became so likeable, even if he is - at times - a cold-blooded murderer.
There's a part of everyone that wants to see Walken as Han Solo, isn't there? It didn't damage Walken's career, mind. He won an Oscar a year later for his brilliant performance in The Deer Hunter.
3rd Year Film and Television Production student at Edge Hill University. Writer of "Stockton's Last Stand" and screenwriter/director of "Hunted" and "Spyfail 2: The Search for Spyfail 1".
I also do stand-up comedy sometimes... I'm told I'm marginally funny.