A political thriller starring Kiefer Sutherland that isn’t a television series played in real time–what an innovation! Unfortunately, “The Sentinel” isn’t clever or exciting enough to serve as a big-screen alternative to “24.”

The premise of the movie is that Pete Garrison (Michael Douglas, in a considerable demotion from his role as the chief executive in 1995’s “The American President”) is a veteran agent in the U.S. Secret Service, one of the guys who took a bullet when John Hinckley tried to shoot Reagan and is now head of the protective detail surrounding the First Lady (Kim Basinger). In the first half of the picture, Garrison–who has a deep, dark (and absurd) secret that makes him an ideal candidate for blackmail–is framed to appear the chief suspect in a plot to assassinate his charge’s husband, President Ballentine (David Rasche). In the second half Garrison predictably goes on the run to clear himself, becoming a fugitive pursued not by U.S. Marshal Tommy Lee Jones but by his own now-estranged protégé David Breckenridge (Sutherland), with whom he’s had a tiff over the younger man’s suspicion that Pete had an affair with his wife, and Breckenridge’s new partner, rookie Jill Marrin (Eva Longoria), whom Garrison just happens to have mentored in “the academy.”

Perhaps the most persuasive aspect of “The Sentinel” is the fact that Rasche plays the president. Rasche was the bumbling Sledge Hammer in the old TV series, and many will feel that he’s therefore perfectly suited to play the chief executive at this moment in our nation’s history, even if Ballentine is one of those schizophrenic fictional prexies who talks tough on terrorism while arguing in favor of the Kyoto Treaty (he might have been named George Blinton or Bill Cush). Otherwise, though, this is one of those movies that starts out seeming very silly and grows more and more preposterous as it lurches along. The secret that makes Garrison a potential patsy is the sort of steamy stupidity that also fueled the flop 1997 tale of White House skullduggery “Murder at 1600,” and the guy’s efforts to keep it under wraps come across as remarkably inept. The rationale behind the assassination plot is murky at best, and when the identity of the actual “mole” inside the Service is finally revealed, it will come as no surprise whatever. Then there’s the big, hugely implausible shoot-out at the close, which suggests that infiltrating a small army of gunmen into an international assembly must be the easiest thing in the world. (At least the meeting is actually set in Toronto, so that the city isn’t forced to stand in for some other metropolis for once.)

The execution certainly isn’t good enough to make you overlook the plot holes and illogicalities. Clark Johnson’s direction seems less assured than it was in “S.W.A.T.” (2003), and he and editor Cindy Mollo muck up the movie not just by allowing the action to go flat far too frequently, but by inserting a flood of “atmospheric” transitional montages (of threatening notes, photos, and other assorted nicknacks) that, taken together, probably extend the running-time by five minutes or so. The performances are pretty much stock, with Douglas going through his usual tight-lipped paces and Sutherland uncharacteristically buttoned-down. As for Longoria, the “Desperate Housewife” star is wasted in a role anybody could have phoned in; an early shot of her behind is a bit of a humiliation, and the most memorable line she’s given to recite is a curt “Copy that!” in response to a radio message. Basinger looks svelte but offers little beyond her appearance as the First Lady, and Martin Donovan is so pallid as the Secret Service’s head honcho that he’s barely noticeable. The various villains are cardboard caricatures. And though Gabriel Beristain’s widescreen cinematography is at least adequate, Christophe Beck’s score swells much too conventionally to be anything other than irritating.

Watchful moviegoers will recognize “The Sentinel” for the ho-hum exercise it is before plunking down any money at the boxoffice. Be on guard against it.