Well, in the original Star Wars, we had an early shot of Luke watching a space battle through binoculars and also talking with his buddy about going to the Academy. Lucas denied this scene existed when it was cut from the re-release just before Empire (just like it always said Episode IV). Pix or GTFO! Um, http://lavender.fortunecity.com/casablanca/95/biggs.jpg
(and http://media.photobucket.com/image/star%20wars%20storybook%20tattooine/jeffr0_/StarWars_01Bonocs.jpg for the comic adaptation)
Lucas denied it until the re-re-re-re-release with added special effects and the return of the Biggs on Yavin scene. Wait, this scene made it back into the film. Lucas finally confessed that the studio made him add the "non-existent" scene, because you don't meet the "hero" for 20 minutes into the film.
This is one guy perpetrating a huge hoax over millions of fans that have turned his movie into a religion.
Now imagine what a branch of the government could do.