10 More Movie Mistakes You Can't Believe You Didn't Spot

Mykelti Williamson gives an unforgettable performance in Forrest Gump as Forrest's (Tom Hanks) tragically ill-fated war buddy Bubba, and one of the character's most distinctive physical characteristics is his prominently protruding lip.

This wasn't achieved by simply having Williamson jut out his lip for the entirety of the shoot, though - he actually wore a subtle lip prosthetic during filming so he didn't have to consciously perform the affectation at all times.

And yet, there's one scene where the production presumably forgot to fit the actor with the false lip. When Bubba and Forrest are riding in a chopper in Vietnam as they go to war, look closely at Bubba and his lip isn't sticking out at all.

Quite what went wrong here is anyone's guess. Hell, perhaps the prosthetic just fell off Williamson's lip during filming and nobody caught it while cameras were rolling. A minor mistake? For sure, but one that'll nag you every time you watch it now.