TriStar Pictures has pulled the plug on its planned production of “The Three Musketeers,” its hand forced by a script that is still being revised and Disney’s competing project that is nearly fully cast and geared to go before the cameras April 15.TriStar chairman Mike Medavoy, who has been insistent all along that the studio was proceeding with its version despite Disney’s plans, acknowledged yesterday, “We don’t have a script that we’re happy with and in this business if you don’t have a script you’re happy with, you don’t make the movie.” Medavoy added that TriStar will be “proceeding to get the script right and if it turns out to be good enough, then we’ll revisit it, otherwise we’ll leave it as it is.” TriStar officials held a meeting Monday to discuss the rewrite the studio received last Friday from Joel Gross. Tuesday, it was decided that the upcoming production, to be directed by Jeremiah Chechik, produced by Allyn Stewart and executive produced by Patrick Crowley, would not go forward since the script was not ready to be sent out to actors with offers. A number of those associated with the project were upset when they received news the production had been canceled. Production designer Dante Ferretti (“The Adventures of Baron Munchausen,”"The Age of Innocence”) had been hired in Europe and a number of below-the-line people, including cameramen and a costume designer, had been lined up. The picture was to begin principal photography May 3 in Paris and then move to Prague. Chechik, who did not have a pay-or-play deal on the picture, met with TriStar management yesterday to discuss other projects. Earlier this month, Disney cast its “Three Musketeers” remake, to be directed by Stephen Herek, with Chris O’Donnell as D’Artagnan and Charlie Sheen and Kiefer Sutherland as two of the three musketeers. One source close to the TriStar “Musketeers” project said yesterday: “They (at TriStar) were unprepared for the fact that they were in a race with Disney and had to develop a strategy. They didn’t have time to improve the script and when Disney had things in solid perspective and put their cast in line, that really shook them up.” The source said four weeks earlier, TriStar brass had acknowledged, “It’s going to be a race with Disney, but said, ‘We’re not concerned, and if it means ours comes out in the summer and theirs at Christmas, so be it.’ Whether that was all lip service…, I don’t know.” For TriStar to have accelerated its pace to keep up with Disney, the source estimated the picture “would have cost $ 45 million all in.” The original projected budget was around $ 30 million. “At that point you’re making a $ 50 million bet that you could get your picture done before theirs. It came down to TriStar was not ready to deal with a competitive duel and go to the mat and Disney had an orchestrated plan of forcing TriStar out,” said the source. Disney’s “Musketeers,” which is being produced by Joe Roth’s Disney-based Caravan Pictures and executive produced by Avnet/Kerner, is said to have a budget of around $ 35 million. The setback of “Three Musketeers” comes on the heels of an earlier blow to Medavoy, who saw Disney beat out TriStar on its production of “The Adventures of Huckleberry Finn.” One TriStar source said, “I wouldn’t be surprised if Fox didn’t re-release its Richard Lester version (of ‘Three Musketeers’) two or three months before Disney releases theirs. It would be unbelievable if they didn’t.” The 1973 hit starred Oliver Reed, Raquel Welch, Faye Dunaway, Richard Chamberlain, Michael York and Frank Finlay.