Disney’s peek at what happened in Oz before Dorothy arrived has just gotten a whole lot more evil and a fair amount witchier as Rachel Weisz is now negotiating to play bad witch Evanora in Oz: The Great and Powerful.

Sam Raimi’s directing the semi-prequel, which finds James Franco as a shyster salesman who ends up carried away to the magical land when his balloon is caught in a tornado.

There, the man who claims to be magical runs into real power when he meets the witches who live there. Theadora (Mila Kunis) is trying to do the right thing, but when her romantic overtures to Franco are spurned, she begins down the path to the dark side, spurred on by twisted sister Evanora (Weisz).

If she signs on, this’ll mark the biggest film Weisz has appeared in for a while and a return to the big effects blockbuster territory found in the Mummy movies.

David Lindsay-Abaire, who wrote the excellent Rabbit Hole, has penned the latest draft of the script, which Raimi will kick off shooting in July.

Weisz was last seen in The Lovely Bones and Agora and has several movies in the release pipeline, including romantic drama The Deep Blue Sea and spy thriller Page Eight.