'Oz's' Journey: 3 Studio Chiefs, Multi-Ethnic Munchkins, James Franco Scores $7 Million

It was while moving forward that Raimi discovered that Warners, which acquired The Wizard of Oz from MGM for its own library, would not allow him to reproduce anything from that picture. To an outsider, it might seem surprising that the filmmakers would get that far along without knowing about the rights situation. Explains Raimi: "The news didn't come in all at one time; it came in drips and drops. We'd hear from the legal department. And then we finally realized, 'Oh no, it can't look anything [like the archetype].' "

Raimi had to reverse course and rely entirely on the 14 Oz-centered books written by Baum and illustrated by William Wallace Denslow in the early part of the 20th century (from which the Judy Garland movie also was adapted), all in the public domain.

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"My first instinct was, there are such iconic images in the Wizard of Oz movie, it would be wrong for us to re-create the Yellow Brick Road or the Emerald City in a different way," Raimi says. "We had to go 180 degrees in the other direction. I thought, 'We're just going to have to make our own Oz.' "

Because it is a prequel, there are no ruby slippers, no Tin Man, Cowardly Lion, Scarecrow or even Dorothy. There's just the much younger Wizard; three witches (Kunis, Weisz and Williams) unlike any in the original; and an Emerald City more reminiscent of art-deco architecture than the Victor Fleming picture's crystalline skyscrapers.

To create this, Raimi hired two-time Oscar winner Robert Stromberg, the production designer behind Avatar and Alice in Wonderland. Together they opted for a combination of actual sets and CGI. "I wanted the actors not to be in a bluescreen stage," Raimi notes. "I wanted them to be in a real place where they could see and touch the set pieces around them and really feel like they were there."

When shooting got under way July 21, 2011, Raimi had to accept compromises for financial reasons, particularly in the number of shots he could stage during the 109-day shoot. The CGI for any five-second shot cost some $40,000, he estimates. One exec told him, "Sam, your storyboards have 1,800 shots; you need to cut that to 1,400" -- because each shot comprised roughly 70 percent CGI.

They filmed inside a converted General Motors plant in Pontiac, Mich., to get tax benefits that lopped off more than 30 percent of the cost to Disney but meant having to ship in vast quantities of materials, from tons of dirt to special foam for statues and other objects.

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Equally hard, from Roth's point of view, was scheduling the cast, many of whom had conflicting commitments. Williams had to promote My Week With Marilyn, while Weisz actually left in the middle of production to shoot The Bourne Legacy before returning to Oz weeks later. Says Roth, "Constructing the schedule was like being an air-traffic controller."

Franco trained with Las Vegas magician Lance Burton. "He came to set for two weeks in Detroit to teach me magic tricks," he says, "but they didn't make the final cut."

At one point, Franco had to leave in the middle of the shoot when his father, Doug, a Silicon Valley entrepreneur, died of a heart attack in September 2011. "We had to stall for three days and shoot with doubles, which was really difficult," Raimi acknowledges. "Then he came back and had to be peppy and filled with charm and do everything the Wizard does."