12 Insanely Subtle CGI Movie Moments Nobody Noticed

3. The Winklevoss Twins - The Social Network

David Fincher strikes again, and while everybody nowadays knows that Armie Hammer doesn't have a twin brother, back in 2010 most audiences flatly assumed that the Winklevoss twins were in fact played by twin actors, because why wouldn't you?

Of course, the twin effect was actually created in post-production, with actor Josh Pence primarily serving as a stand-in for Tyler Winklevoss on-set before Hammer's face was digitally pasted over his. In some sequences, more straight-forward split-screen blending was used to combine separate takes of Hammer playing each of the twins.

There's never a moment where the mask slips, pardon the pun, which is a testament not only to the startling effects work, but also to the brilliance of Hammer's exceptional dual performance.