In order to accurately answer this question, one must first understand who Charlize Theron is and what she looked like before her transformation. Charlize Theron is a South African-born actress and producer. She rose to fame in the late 1990s and early 2000s with films such as The Devil's Advocate (1997), Mighty Joe Young (1998), and The Cider House Rules (1999). For her work in Monster (2003), she won the Academy Award for Best Actress, becoming the first South African to do so.
In recent years, Theron has taken on more action-oriented roles in such films as Mad Max: Fury Road (2015) and Atomic Blonde (2017). She also produced the latter film. In 2019, she starred in the lead role of Megyn Kelly in Bombshell, a film about the sexual harassment scandal at Fox News.
So now that we know who Charlize Theron is, let's take a look at how they transformed her for her role in Bombshell. In order to make Theron look more like Kelly, the makeup team had to give her freckles, darker eyebrows, and lighter hair. They also had to change her teeth slightly by adding veneers. All of these changes helped create the illusion that Charlize Theron was Megyn Kelly.