(Cover) - EN Showbiz - Michelle Williams always follows her heart when it comes to movie roles, as shes a glutton for punishment.

The American actress is well known for taking on difficult parts, and plays Marilyn Monroe in upcoming film My Week with Marilyn. The picture is about the relationship between Marilyn and Sir Laurence Olivier, and Michelle studied the actress life as much as possible before shooting began to ensure she did her justice.

Michelle knows many would shy away from playing such an iconic person, but says pushing herself is what drives her. Im a glutton for punishment! I wont let myself shrink away from a challenge. While my mind is saying, Retreat, retreat, retreat! my heart is already there and thats what ultimately wins, she explained.

The actress starred alongside Ryan Gosling in recent release Blue Valentine, which charted the relationship between their characters Cindy and Dean. Much was made of the pairs screen chemistry, which was so strong some people believed they were an item in real life too.

Michelle explained they were told to totally immerse themselves in their characters lives, which is why their performances were so strong.

We were driven to a house where our characters find themselves married with a young daughter and told, Make it a home, she explained to Look magazine. We were allowed to make decisions about how to decorate it so we went to a studio to have our photos taken and hung them on the wall. We grocery shopped, cooked, cleaned our dishes, took out the trash... We made home movies. We made memories as a couple. We did everything but share the marital bed! (C) Cover Media