Movie magic can accomplish anything these days. Takes this example. During the post-production of Rogue One: A Star Wars Story, the crew was labouring over the digital recreation of "Governor Tarkin."
Another employee, not too familiar with Star Wars, asked why they were so concerned with the actor's skin and lips, not realizing that the character on the screen was a product of CGI.
But sometimes, the unthinkable happens and special effects are needed if a main actor passes away during the production of a movie. Tragically, this has happened on more than a few occasions.
To hear about such examples, please watch the video above.