Michelle Williams views herself as "some other being" when she watches her movies.

The 31-year-old actress is being tipped for an Oscar for her convincing portrayal of Marilyn Monroe in 'My Week with Marilyn' but she insists she sees neither the character nor herself if she sits through her films when they are complete.

Asked if she sees herself as Marilyn on screen, she said: "Oh, gosh, I don't know. I've sort of - I don't really know who I'm looking at any more. It's just kind of at her. Whenever I see it, it's a she or a her. It's not me. And I wouldn't be audacious to say it was Marilyn. It's just some other being. It's a strange relationship. "

Despite portraying an iconic sex symbol in the movie, Michelle insists she didn't always feel sexy during shooting.

Speaking on CNN show 'Piers Morgan Tonight, she said: "Honestly, no [I didn't feel sexy]. You know, maybe in those kind of moments - in the moment with the bathtub or a scene with the school boys. But not consistently. Not in your every day life, not on the weekends when all that comes off, The Hair, the wig, the costume. There's some sort of strange in between person underneath."