Sam Raimi's 'Oz: The Great and Powerful' begs one essential question: Which witch will become the infamous Wicked Witch of the West? While we all know Michelle Williams, who plays Glinda in this 'Wizard of Oz' origin story, won't be taking to the broom anytime soon, there's still the pair of sister witches, played by Rachel Weisz and Mila Kunis, to worry about. So, which actress is secretly the bane of Oz? Spoilers await after the jump.

You may already know the Wicked Witch of the West's identity in 'Oz: The Great and Powerful' based on the rumors circulating throughout the webosphere, or you have your own theories, but so far Disney has tried to keep us in the dark as to not spoil the presumed "big reveal" of the film. However, it looks like they either decided we've been waiting long enough or they have inadvertently revealed the answer too soon.

[WARNING: If you prefer to wait for the answer in theaters, you can still turn back now!]

We don't normally turn to coffee mugs for the latest movie news, but that's where we're headed. First brought to our attention by an intrepid AICN reader, the official Walt Disney store now has 'Oz: The Great and Powerful'-themed merchandise, including some coffee mugs that feature "The Wizard" Oscar Diggs (James Franco) and an up-close look at the Wicked Witch of the West!

And the actress portraying our green-skinned friend is...

... Well, clearly it's Mila Kunis!

The actress previously teased that each of the characters in the film will go through transformations of sorts, but that hers wouldn't have children running up to her -- this is in addition to an exclusive report Vulture ran outing Kunis as the Oz deviant back in 2011. Sorry if you were hoping it'd be Weisz, but pics don't lie.

'Oz: The Great and Powerful' hits theaters March 8th, and you can watch the latest TV spot below:

On a side note, if you want to purchase this mug, click on over to the Disney Store.