Mysterious witch poster emerges for new 'Oz' film

Is it the Wicked Witch of the West? Or the Wicked Witch of the East?

A new poster for Sam Raimi's 'Wizard of Oz' prequel 'Oz the Great and Powerful' has been released featuring a mysterious witch.

Disney is keeping quiet over which witch it is, but it's either Rachel Weisz, who is playing Evanora, the Wicked Witch of the East, or Mila Kunis, who is playing Theodora, the Wicked Witch of the West.

[Related story: Oz the Great and Powerful - stunning new trailer]

Which witch?... new poster revealed for Oz film (Copyright: Disney)

Though Kunis is playing the Wicked Witch of the West, the green-hued harridan from the original film, there's debate among fans over whether this is Rachel Weisz's character, the Wicked Witch of the East, who is not actually seen in the original 'Wizard of Oz' film.

Whatever the identity, Raimi's take on the world of 'Oz' is already hotly-anticipated.

With the director's origins in horror, it's likely that the film will have a decidedly dark edge to it.

James Franco is playing Oscar Diggs in the prequel, an ethically dubious magician who is whisked away to Oz and presumed to be the Wizard, whose arrival is prophesied.

But the witches Theodora, Evanora and Glinda, played by Michelle Williams, are less convinced.

The film also stars Zach Braff, who voices a flying monkey, and Bruce Campbell, who plays dark wizard Gore.

It's out in the UK on March 8.