10 Astonishing Things You Didn't Know About Iconic Movie Scenes
2. Linda Hamilton's Twin Sister Was Used For The Scene Where The T-1000 Imitates Her - Terminator 2: Judgment Day
Given how much awesome CGI there is in James Cameron's first Terminator sequel, it would be safe to assume that CGI was used to pull-off the shots where there needed to be two Sarah Connor characters on-screen at once, as a result of the shape-shifting T-1000. After all, if Cameron managed to render a liquid metal robot assassin, he could achieve something like that with ease, right?
In reality, Cameron opted for a different technique - an incredibly logical one that probably saved a lot of time and effort: he just used Linda Hamilton's real-life twin sister, Leslie, in the background shots.
The same technique was used in an earlier scene when the T-1000 becomes a prison guard.