Paige and Leo, the beaming marrieds played by Rachel McAdams and Channing Tatum at the beginning of The Vow, step out of the venerable Music Box cinema in Chicago, into the snowy night.

There's no close-up of the marquee, or of the posters on the street, to indicate what they've just seen, but here are some suggestions: Memento, Regarding Henry, Random Harvest, I Love You Again, any of the Bournes.

Yes, The Vow is an amnesia movie, a slathered-with-sentiment romance in which the perky Paige goes flying through a car window and awakens from her coma (lots of intercranial hemorrhaging) unable to recognize the man she adored.

There's Leo at the foot of the hospital bed, his mouth agape: His wife opens her eyes, peers uncertainly in his direction, and addresses him as "Doctor."

And so, in the impossibly corny The Vow (impossibly corny, yes, but "inspired by true events"), Leo has to woo Paige all over again. She doesn't remember the loft they shared, or their coffee-making morning ritual. She doesn't remember her art studio, or the sculpture she's been commissioned to make. Or the fact that she's a vegetarian, and has a tattoo on her back (no, it's not a dragon).

The bigger problem is that the spark between Paige and Leo doesn't seem to be there anymore. (Speaking of sparks, both McAdams and Tatum are veterans of similar mush adapted from Nicholas Sparks best sellers: She: The Notebook. He: Dear John.) Paige returns home to her uptight, upmarket parents (Sam Neill, Jessica Lange), puts unflattering highlights in her hair, finds her old preppy clothes, and reengages with her pre-Leo beau (Scott Speedman).

She's stuck in "old me" mode - there's a patch of near-parodic dialogue in which Paige rambles on about "the old me" and "the new me." There wasn't an artsy bone in her body back then. She was enrolled in law school. She was Daddy's little girl.

But Leo, who runs a recording studio, is not giving up. "I've got to make my wife fall in love with me again," he tells his coterie of chums, a genial gang of homogenized hipsters, as they shuffle down the street. He takes her back to the wine-and-chocolate spot that was the site of their first date. (Cafe Mnemonic, it's called - they wrote their wedding vows on its take-out menus.) He drives her to the secluded swatch of lakefront where they used to go skinny-dipping.

And he cries man tears.

McAdams and Tatum aren't exactly thespian heavyweights, but even if they were, there isn't much they can do with this hokey melodrama, beyond playing it straight, playing it sincere. It turns out there's a dark secret lurking in Paige's traumatized psyche, and its third-act revelation upends "the full do-over" Paige feels like she's been granted in life.

Ready-made for Valentine's Day, The Vow is, like the offerings at Cafe Mnemonic, a total sugar overload.EndText

Contact movie critic Steven Rea at 215-854-5629 or srea@phillynews.com. Read his blog, "On Movies Online," at http://www.philly.com/philly/blogs/onmovies