7. Young Flynn/Clu - TRON: Legacy
I have to hand it to Joseph Kosinski and the team over at Digital Domain - they really did try to make us believe that a young Jeff Bridges was walking around in The Grid, but even with low-key lighting, it was still painfully abundant that we were looking at a CGI doppelganger. In order to recreate a young Bridges for both scenes featuring a young Kevin Flynn and the Grid counterpart Clu, DD borrowed his likeness from the 1984 film Against All Odds (to imply that he had aged a few years since 1982's original TRON), and spent over two years tailoring this model to Bridges' own facial performance on Legacy's set. It was an arduous process, though sadly one that wasn't really worth the time spent on it; the second we see Kevin Flynn talking to his young son in an opening flashback, we know that we're seeing an animated object, again because the eyes and facial animations can't quite replicate a human being convincingly. At least with the character Clu, his existence as a digital object within the context of the story makes us care less about him being an inexact replica...