In Spartan, the latest David Mamet thriller that works overtime to pull the rug out from under itself, Val Kilmer holds his face as blank as an automaton's, and his hair is so rigid it's practically square-jawed. Kilmer plays some sort of very special, very tight-lipped military agent who is charged with locating the President's daughter. It turns out that she may have been forced into a sex-slave ring filtered through the Arab city of Dubai. Kilmer, acting like a joyless James Bond, gets to bark out a lot of stylishly stiff, machine-gun Mamet lines like ''The girl's in the house. I'm taking her out. If it ain't me or her, kill it!'' At a roadside gas station, Kilmer and his cohort (Derek Luke) shoot a convenience-store worker, then a cop, then one of the death-row inmates the cop was transporting. The incident isn't quite as vicious as it appears; it's really an elaborate ruse designed to scare the other inmate into talking. When you consider, though, how many simpler ways there might have been to achieve that same goal, it's clear that the real purpose of the charade is that David Mamet dreamed it up and thought it would be fun to stage.
In the past, Mamet's entertaining shell-game thrillers (''The Spanish Prisoner,'' ''House of Games'') had little to do with the real world, and that, along with the author's trademark terse, look-ma-no-feelings dialogue, was part of their hard-boiled pleasure. ''Spartan'' is different. It's a political thriller set within the cynical nexus of presidential image making and tabloid gossip. It tells us, for example, that the First Daughter was abducted from Harvard when the President arrived in Boston for an evening of ''tomcatting'' and took away her Secret Service agents, leaving her unprotected. But does Mamet really expect us to buy this for even three seconds? Aren't there enough agents in the United States to cover the President and his daughter for a single evening? In ''Spartan,'' the tail of Mamet's imagination too often wags the dog of plausibility.
White slavery, a murderous White House cover-up, a team of high-surveillence operatives led by William H. Macy as a human walkie-talkie: Spartan may be the first Mamet movie in which the upended genre conventions start to spin into Hollywood conspiracy clichés. The Mamet touch lies in the way he leaves conventional expository scenes on the cutting-room floor; he wants the audience to work at putting those clichés together. ''Spartan'' is just cryptic enough to keep you guessing, and for some viewers that may qualify as a night out. But Mamet's gamesmanship was more fun when it was less eager to look important.