4. Peter Weller/Robert John Burke - RoboCop
Granted, RoboCop spends much of his screentime concealed beneath that iconic suit, but that's not to say it isn't important that we at least
know that there's a man in there somewhere. When
RoboCop 2 came out to less than satisfactory standards, the original actor - Peter Weller - decided that he wasn't up for the third installment, so the filmmakers - determine to keep the franchise going - simply recast the role. His replacement? An actor named Robert John Burke. Though most people probably weren't that bothered about who had been beneath the suit the whole time, given that we don't really see much of that person anyway, one simple fact remains: you take that kind of thing for granted until - whoosh - one day it's gone. That's to say, Robert John Burke simply wasn't Peter Weller. And because we knew that, it made it nearly impossible to care about
RoboCop 3 at all. We went on a journey with Weller, suit and all. Burke is mere imitation.