One of the biggest films on Walt Disney Studios' slate -- starring perhaps its most important actor -- has come to a screeching halt, TheWrap has confirmed. Disney has stopped pre-production on "The Lone Ranger," which was -- or is -- to star "Pirates of the Caribbean" toplinerJohnny Depp as Tonto. An individual close to the project told TheWrap Friday night that everyone involved with the movie is "talking about next steps." Another speculated that the decision could be a ploy on the studio's part to reduce the budget. That's not entirely unlikely, as studio head Rich Ross entered the job with a mandate to cut costs. There are all kinds of reasons Disney would tread gently with this: In addition to the Depp heft, there'sJerry Bruckheimer's producer heft and Gore Verbinski's director heft. The studio does not want to anger Depp, who stars in its most successful franchise -- and whose "Alice in Wonderland" grossed more than $1 billion worldwide for the studio. Disney would like Depp to make a fifth "Pirates." Verbinski, who is attached to direct "The Lone Ranger," directed Depp in"Rango" and in three "Pirates" films. Bruckheimer produced the "Pirates" movies.