The filmmakers may have taken precautions, but the raw, exhilarating “Fight Club” could still blow up in their faces. The movie, based on a Chuck Palahniuk novel, will open on Oct. 15. Fans of Fincher’s who’ve seen advance screenings are already on the Internet calling it a “masterpiece,” as well as “angry, savage and out-there.” Others will be scandalized. At a time when Hollywood is being criticized for violence–a time when Warner Bros. and Oliver Stone are being sued for shootings supposedly inspired by “Natural Born Killers”–Fincher and Twentieth Century Fox have made a $70 million movie that could be misinterpreted as a primer on anarchy. “Fight” pushes hot buttons with both hands: rowdy sex, violence, terrorism, political disaffection. “I pray Washington doesn’t want kids to see this,” says a source close to the movie. “What better way to sell it?”

But that cynicism masks a nervous studio. Fox knows “Fight Club” may be too gruesome to be a blockbuster. Asked how much the movie will likely gross, a second source inside Fox says it will be lucky to make even $65 million. Originally, “Fight Club” was meant to be a summer flick–the big-budget reunion of the director and star of “Seven.” Then came Littleton and Atlanta. Fox insists they moved the movie out of the summer because it wasn’t finished. Laura Ziskin, a top executive, rightly raves about how smart and provocative the movie is. Still, sources say Fox wasn’t fully prepared for how dark “Fight Club” would be.

After meeting on the plane, Tyler and Jack form a secret club. Members meet in a dank basement and beat the daylights out of one another in a kind of religious ritual meant to purify them from the soul-destroying effects of mass society. Screenwriter Uhls claims he’s already heard of a few fight clubs starting up. Let’s hope nobody emulates anything else in the movie. For their part, Fox and Fincher see “Fight Club” as a thinking-man’s mayhem (women are not likely to be fans, Pitt’s physique notwithstanding). “I don’t think it’s a good thing to protect people from ideas,” says Fincher. “You should educate people about the repercussions of violence. This is a moral movie–every bit as moral as, say, ‘MAS*H’.” Convincing everyone of that may be an ugly fight.