Mila Kunis joins Oz, the Great and Powerful

Mila Kunis has signed up for 'Oz, the Great and Powerful'.

The 'Black Swan' star will play witch Theodora in the 'Wizard of Oz' prequel, opposite James Franco as the titular wizard.

The movie tells the tale of a con man who runs away from a travelling circus in a hot air balloon, only to wind up in Oz, a land where magic is real.

Theodora is one of a group of witches - and the sister of good witch Glinda - who becomes evil when her sexual advances are turned down by James Franco's character.

Sam Raimi is directing the project, and is currently looking to cast other leading females, with Variety reporting Keira Knightley, Olivia Wilde and Kate Beckinsale all under consideration.

Ukrainian-born Mila will next be seen with Justin Timberlake in 'Friends with Benefits' and next year will play the role of Lori in 'Ted', about a man whose teddy bear comes to life as a result of a childhood wish.