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

Six years later, however, Kapner mentioned the idea to Roth's colleague (and now Oz's executive producer) Palak Patel, who was as enchanted as the writer. After pitching it to Sony and getting a thumbs-down, they went to Disney, where Cook and then-studio president Oren Aviv commissioned a screenplay.

Almost immediately, the project became shrouded in secrecy. It was even given a code name, Brick, because Disney feared other studios would fast-track the slew of Oz-based projects already in the works, including Universal's movie version of Wicked and another picture at New Line Cinema.

"It was so top-secret," Kapner recalls. "My wife knew, and two of my closest friends, but they were sworn to secrecy on pain of death."

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This secrecy endured until Kapner turned in his script at the end of 2009, and Roth set out to hire a director. Finding the right person was anything but easy; he knew few filmmakers would risk their reputations on a vehicle that inevitably would be compared to a classic -- one the Library of Congress has named the most-watched film of all time.

Then, as Roth and Patel were compiling a list of potential helmers, Raimi heard about the script. The 53-year-old director had spent years honing his craft with genre movies such as the Evil Dead series, the Coen-esque thriller A Simple Plan and the Western The Quick and the Dead before vaulting to Hollywood's A-list with his Spider-Man trilogy. Having wrapped a return-to-form horror film, Drag Me to Hell (2009), he was looking for a new challenge.

Initially, he had hesitated to read Kapner's draft, afraid it would color his perception of the masterpiece. But when he read it, he realized, "Oh, it's not just treading on the good name. It's its own story, and one that I really liked."

Roth, who had been Raimi's neighbor on the Sony lot, was thrilled. "There are very few guys who have both the heart and technical expertise to fulfill this stuff," he says.

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After he officially joined the Oz enterprise in early summer 2010, Raimi launched into months of work on the screenplay. Entire characters from the original script were eliminated (including a tribe of humanoid knives and forks) and new ones added, among them Knuck (Tony Cox), a Munchkin who doesn't appear in the novels. "The little people are represented in a good light," says Raimi. "In the world of 2013 Oz, it's a multi-ethnic look."

More crucially, he further refined the character of the Wizard, who also bears the name Oz, and hired Pulitzer Prize winner David Lindsay-Abaire (Rabbit Hole, Rise of the Guardians) to help him. "Sam wanted the story to be more emotionally driven," says the writer. "It became about a selfish guy who learns to be selfless."

That guy was younger than Franco had anticipated. "The character was in the 1939 film, but he was an older man," the actor says. "I was a little less nervous when I realized that I had the freedom to create a new character."