Stepping into a character is a difficult process, and anything that gives you an edge helps. The cast of The Social Network, for instance, praised the sets on the film because it made them feel like they were at Harvard and it helped their performances.
Likewise, looking into a mirror and seeing yourself as someone else helps too. The New York Times has a piece about the use of wigs in movies and mentions that the Marilyn Monroe wig used on Michelle Williams in My Week with Marilyn cost a whopping $4,000. That’s the cost of getting an Academy Award nomination, it seems.
But why not save the money and style their hair? Well, Williams’ hair was much too short to style at the time. Waiting for her to grow it out would add time to the development of the movie, which would hurt anyone that had a project lined up after My Week with Marilyn. The easiest thing to do is to simply use a wig.
Sean Flanigan, who styled Katherine Heigl’s wig in One for the Money, also points out that wigs can be used when styling the actors hair would just take too long. For instance, they would have had to style Heigl’s hair every day and get it exactly the same (curly) for her character. Instead of that, they chose to simply give her a wig that stays the same the whole time. Easy. [New York Times via Moviefone]