|Natalie Portman in Dior ad.|
It is called Sex, and is part 1 of the "Sex, Drugs and Natalie Portman" trilogy.
No, it is not erotic. Not really. Well, maybe a little bit.
The director is Chad Peters.
More info here.
Speaking of Natalie Portman. She has actually performed one of the most groundbreaking gender bender videos ever invented.
The second video below is censored, but contrast between this sweet girl and her aggressive masculine moves and rapping is thought provoking.
UPDATE: Sorry! It seems the maker of this movie has removed all online files since I prepared this post (I often write posts long before they are published).
Apparently there is a full length remake called Apocalypse, CA, but to be honest with you, I do not see the similarities, although there is supposed to be a similar body switch!