LOS ANGELES  - Robert Downey Jr. has fallen out of "Oz, the Great and Powerful," Disney's prequel-ish take on the "Wizard of Oz" tale, and the studio is in talks with Johnny Depp to don the great wizard's robe.

The story revolves around a showy young illusionist who is forced to flee a traveling circus. His hot air balloon is swept up by a tornado to the land of Oz, which is run by two magical wicked witches. Sam Raimi ("Spider-Man") will direct.

While it doesn't have a start or release date, the project is a high priority for Disney, which hopes to start production in the second half of the year.

Depp has a close relationship with the studio after starring in its "Pirates of the Caribbean" films and last year's "Alice in Wonderland." The issue is timing.

He is scheduled to begin shooting "Dark Shadows," Tim Burton's adaptation of the 1960s gothic soap opera, for Warner Bros. this spring. Depp is also attached to star as Tonto in Disney's "The Lone Ranger." That project is further back in the development process than "Oz," although it has a director, Gore Verbinski ("Pirates of the Caribbean").

Disney clearly would love for Depp to do both, but if he commits to "Oz," that pushes Ranger back even further.

Downey, meanwhile, seems to freeing up his dance card for 2011, with "Oz" the second project he is backing away from. The actor was to star in "Gravity" opposite Sandra Bullock but dropped out in November.