McDiarmid had to undergo hours of facial prosthetics and makeup to complete the transformation into the crazed villain. All that power went to his head and aged him quite a lot!
Maleficent - Angelina Jolie
Apparently, Angelina Jolie was so good in this role that she scared her own daughter, who was also filming on set at the time. Jolie had to undergo a lot of makeup to truly get into the role. The angular facial features were made possible by prosthetics!
A good amount of CGI was also used on Jolie to make the villain even creepier. After all, someone who is trying to kill Sleeping Beauty has to look and feel like a total monster. Maleficent is probably Jolie's creepiest role to date.
Captain Phasma - Gwendoline Christie
Star Wars: The Force Awakens paved the road for tons of new characters, including major villain Captain Phasma. The character was originally written as masculine/male, and most viewers assume that the people in the Storm Trooper suits are male. With Phasma, that is not the case.