Any great actor should be able to transport their audience to a new realm of reality. A place where they keep their disbelief in suspense thanks to the riveting performance they see before them. Often, however, a performer is in need of a small helping hand to make their character feel a little more authentic. Makeup is used in each and every film, whether you’re Steve Carell in The 40-Year-Old Virgin or Marlon Brando in The Godfather, with such being necessary to make the skin appear less glossy and sweaty on camera. Usually, this will only mean a little touch-up here and there, but in other cases, more dramatic transformations may be necessary to give the respective actor a new face entirely…
Source: The 10 craziest makeup transformations in cinema history