Oz sequel already in the works

Despite barely being in cinemas yet, a sequel to 'Oz: The Great and Powerful' is already being planned, according to reports.

Variety reckons that writer Mitchell Kapner – who penned the Oz prequel with David Lindsay-Abaire – is working on a follow-up.

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The movie industry paper also suggests that Kapner was in fact hired 'several months ago', meaning that a second film was always on the cards.

Luckily, Sam Raimi's extremely expensive movie - it's thought to have cost Disney $325 million with its marketing budget - is forecast to be a hit when it opens at the weekend, with a predicted $80 million opening in the US.

Kapner is able work on material from Oz writer L. Frank Baum's novel 'The Wonderful Wizard of Oz', as it is now in the public domain.

But no mentions of such items as Dorothy's ruby slippers from the 1939 film are allowed, as that intellectual property is owned by Warner Bros.

Whether director Raimi would be involved in a second film is unsure, however.

"It was really this particular story that appealed to me and I don't know if that would exist in another sequel or not," he has said.

'Oz: The Great and Powerful' is out today (March 8), starring James Franco, Mila Kunis, Michelle Williams and Rachel Weisz.