As terminally precious as any Meg Ryan vehicle, the time-travel romantic comedy "Kate and Leopold" might warm the easy heart, but it will most certainly numb the brain.

Ryan is talented but seemingly trapped by her demographic appeal in a perpetual loop of cutesy-poo chick flicks. It's something of an ironic joke that this time out the actress plays a market researcher who is introduced while rolling her eyes in the back of a movie theater during a test screening of an appallingly sappy romance.

A flustered Manhattan career gal whose love life frustration is amusingly amplified by her amateur inventor ex-boyfriend (Leiv Schreiber) living in the apartment above hers, Kate McKay (Ryan) has lost all patience with the ex when he excitedly claims to have discovered a portal into the 19th Century -- and returned with his great-great-grandfather in tow. Stuart (Schreiber) then introduces the handsome, princely, mister fancy-pants as Leopold, the third Duke of Albany (Hugh Jackman), and Kate doesn't believe a word of it.

We the viewers know it's true, however, because the movie opens with a humorous 1867 prologue in which an agog Schreiber tries to look inconspicuous while scribbling mad notes and taking pictures with a spy camera in a crowd watching the construction of the Brooklyn Bridge. He's also witness to Leopold's discovery that his family is living off their good name so he's going to have to marry for money.

Unfortunately, that little plot device (which is never resolved) is only the beginning of the hackneyed and loosely-adhered gimmickry in this picture, which takes a turn for insipid when the story moves into the present.

Although entirely unconvinced of his antiquated origins, Kate finds herself falling for Leopold after they're left alone when Stuart takes a tumble down an open elevator shaft, winding up in the hospital. Leopold, it seems, was the inventor of the elevator, so when he jumped forward in time, every lift in the world stopped working -- a fact that is hard to grasp since this story element has been inexplicably, conspicuously and clumsily edited out of the film.

Schreiber -- who gives the funniest, most natural performance in "Kate and Leopold" -- has also been deleted from the better part of the picture (nobody even visits him in the hospital) to keep the focus on our time-crossed lovers. They frolic through obligatory stranger-in-a-strange-century clichés (thankfully kept to a minimum), courtly candle-lit dinners and other modern misadventures, while Kate takes the better part of the five reels to catch on that Leopold truly is a time traveler.

On top of its blatant post-production gutting of pivotal plot points, "Kate and Leopold" must ply its characters with a certain witlessness to sustain the story and frequently stumbles over Leopold's inconsistent sense of formality. Asked his name, he replies, "Leopold" (not "I am Leopold, the Duke of Albany") and is happy to go by "Leo." Yet confronted by a beat cop while walking a dog that does his business on the sidewalk, he sniffs, "Are you suggesting, madam, that there exists a law requiring gentlemen to lay hold of canine bowel movements?"

Director James Mangold ("Girl, Interrupted") also assumes the Kleenex-toting target audience for this picture won't mind the willfully sloppy science fiction, which requires suspension of disbelief on a level that action movie directors can only dream of. Time travelers pass between eras by jumping off the Brooklyn Bridge and falling into a temporal rift, for example. But what happens after they jump? Where and how do they land? The director doesn't care because it's just cheap cinematic subterfuge.

The movie's inevitable happily-ever-after ending is equally burdened by such blatant absurdities and unresolved plot gimmicks. But out of deference to those who don't trust this review, I won't go into them here. Suffice it to say, "Kate and Leopold" is annoyingly disinterested in being anything beyond cute.