Jessica Biel  hair purse blazer pantsJessica Biel has ditched her sun-kissed locks for a very serious shade of chestnut brown.

The actress-turned-director (she's directing a short for Glamour's Reel Moments series), has been hoofing it around town solo while boyfriend Justin Timberlake shoots Friends With Benefits.

We certainly hope she didn't pull one of those needy girlfriend moves and change her hair just to get his attention! Although we suspect the change has a lot more to do with her role in new thiller The Tall Man, which starts shooting at the end of the month, where she'll play a desperate mother who is searching for her missing child.

Sounds like fun!