As an actor, it is extremely important to commit to a role, and not only make it yours but become the character. Some of the most successful actors in the business know this, and work hard to achieve this. And some of the most rewarded peers know that commiting to a role not only involves changing your demeanor; being an actor sometimes also means you need to become someone else for the role.

Here is a list of incredible actors and acresses who have made unbelievable character transformations, proving why they are some of the best in Hollywood.