04/04/2014 07:38 BST | Updated 04/04/2014 07:59 BST

Jennifer Aniston Is Unrecognisable As She Goes Brunette And Make-Up Free On The Set Of 'Cake'

When we first clapped eyes on these snaps of Jennifer Aniston we must admit we were just a little bit pleased to see the actress looking, well, more Hounslow than Hollywood.

But of course, despite Jen resembling what we look like first thing in the morning, all it is not quite as it seems.

Jennifer Aniston

Don't let it be said that the former 'Friends' star isn't willing to suffer for her art because Jen's make-under of mousy hair, a slap-free face and slobby clothes are all for her role in her new film 'Cake'.

The star was spotted on-set in Pasadena, California filming the forthcoming movie, which also stars 'Avatar' star Sam Worthington.

According to IMDB.com, the story follows 'a grieving mother suffering from chronic pain in the aftermath of a fatal car accident finds an unlikely source of inspiration.'

We're guessing she hasn't got to those scenes yet.

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