One of the coolest effects that I’ve seen, in movies, is in Forrest Gump. They convincingly, put Tom Hanks into several real, historical, event film clips. It’s an effect that we don’t see very often, and when done well, is very impressive. Check out this tutorial that shows how to do the effect, step-by-step.
Original Article: http://nofilmschool.com/2015/08/tutorial-achieve-forrest-gump-effect-just-8-steps