If you remember last summer, Robert Downey, Jr. suffered an ankle injury while filming 'Iron Man 3' and the production hit some delays. Marvel didn't want to shut down and risk missing the May 3 release date, so they decided if they couldn't have Robert Downey, Jr. they were going to do the next best thing: make a fake Robert Downey, Jr. Did you spot Fake Tony Stark in the movie? We'll show you where and how below.

Robert Downey, Jr. was going to be out of commission for six weeks as he recuperated from a broken ankle he injured on the 'Iron Man 3' set. Six weeks is an eternity in the world of film production (most movies are completely wrapped in that amount of time) so to keep the production from grinding to a halt, they continued to film 'Iron Man 3' without their star. Sometimes they would shoot scenes that didn't require Tony Stark but in other cases, they just built themselves a brand new Robert Downey, Jr.

Says 'Iron Man 3' VFX Supervisor Chris Townsend, "We were able to reconstruct [Robert Downey, Jr.] as Tony Stark on set, with the help of [a] body double and the facial captures we’d collected afterwards."

The production teamed up with Weta Digital ('Lord of the Rings') and essentially created a digital body double that would be inserted into the movie. Remember the final sequence of the film that was shot on the beach? That wasn't Robert Downey, Jr., that was a computer created version of Robert Downey, Jr.

What they would do was film the scene with a body double that matched Downey's height and build. The face of the double would be replaced with a capture of Robert Downey, Jr.'s face recorded in post-production. The two would be merged to create the illusion that Robert Downey, Jr. was on set while in reality he was at home healing his broken ankle. (It's similar to how Marvel created "Skinny Steve" in the original 'Captain America.') There were some scenes where an entirely digital double was used. And neither us, nor anyone else who saw the film, was the wiser.

There's more on the VFX of 'Iron Man 3' in this new article including how they created that army of Iron Men for the film's finale.

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