When the trailers for "Jack and Jill" were released, starring Adam Sandler (2011's "Just Go with It") in the dual roles of a bickering twin brother and sister, audience reaction more closely resembled a disbelieving outcry (that it is destined to be a big hit regardless may give it the last laugh). It is true that the film, based on its general sheen and advertising, looks more like one of Sandler's character's asinine fictional comedies glimpsed in 2009's "Funny People" than a legitimate, honest-to-goodness motion picture, but that also appeared to be part of its possible charm; even if it was terrible, it would likely be an entertaining kind of terrible or, at least, an offbeat curiosity. And, if it turned out to not be bad at all—a knowingly ridiculous idea so crazy it works—then all the better. Alas, "Jack and Jill" is more "Norbit" than "Tootsie" or "Mrs. Doubtfire." It's got its moments, to be sure, but director Dennis Dugan (2010's "Grown Ups") and writing trio Steve Koren (2006's "Click"), Robert Smigel (2008's "You Don't Mess with the Zohan"), and Ben Zook seem to be slumming it, under the false assumption that a clever, fully-formed screenplay is unnecessary as long as their leading man is in a wig and dress. If only quality moviemaking was that easy.

42-year-old ad executive Jack Sadelstein has a lovely family—wife Erin (Katie Holmes) and children Gary (Rohan Chand) and Sofia (Elodie Tougne)—and a beautiful L.A. home. His job has its pressures—one of the company's biggest clients Dunkin' Donuts is threatening to walk if they don't get Al Pacino to star in their upcoming Dunkaccino campaign—but it's the kind of stress he's adept to handle. What Jack has never been quite so smooth about is dealing with the annual Thanksgiving visit of his abrasive Bronx-based sister Jill (Sandler again). Her trip is supposed to be for four days, but as Jack predicts and dreads, she decides to prolong her stay through Hanukah, and then perhaps even longer than that. Jack is so busy trying to pull away from the natural bonds they do share as siblings and twins, it is a long time coming when he discovers just how lonely and needing of acceptance Jill really is.

Cross-dressing comedies are practically a rite of passage that every comic actor must attempt at one point or another in their career. When it is pulled off well, it makes for terrific fodder. In addition to the aforementioned Dustin Hoffman and Robin Williams starrers, the underappreciated likes of 1992's "Ladybugs," 2002's "Sorority Boys," and 2006's "She's the Man" have all been formidable entries within the gender-bending subgenre. "Jack and Jill" is more scattershot than all those, slapped together by a cut-crazed editor who has seemingly tossed aside every other filmed scene (several in the trailer are nowhere to be found in the finished product) in a mad dash to get to the end credits. It's not that the film feels all that short—though at 89 minutes, it is on the brisk side—but that the story is missing gaps in its narrative, taking its almost exclusively paper-thin characters through Thanksgiving, Hanukah, the twins' birthday, a holiday cruise, and New Year's Eve with barely any cohesion or sense of time and place and atmosphere outside of what's being blatantly spoken in exposition. It's a waste of a lot of great locations, including the cruise ship Allure of the Seas, which the production was granted permission to shoot upon and is made to feel like an afterthought.

Adam Sandler is obviously having fun, and it is his endearing spin on brother and sister Jack and Jill that keeps the film watchable. Aims at humor aren't choicy and run the gamut, but it would be lying to claim there are no laughs. From a one-toothed Hispanic granny who keeps getting brutalized and brought back to consciousness by hot peppers being shoved in her mouth, to a gastrointestinal ordeal following Jill's first-ever Mexican meal, the movie holds no pretensions that it's anything other than the silly, immature comedy it is. That's not to say there aren't some slyer, less broad gags. An ongoing bit where Jill can't remember the titles of well-known classic movies is a hoot, and so is Jill's supposed jet lag after flying from the East to West coast (a time difference of three whole hours!). Somehow, the sweat shadow she leaves behind in her bed bears scrutiny. Sandler is actually playing three roles here—Jack, Jill, and Jack posing in drag as Jill—and they are three very specific characters that illustrate the diversity Sandler's capable of even in lesser projects like this. Furthermore, Jill may not exactly be prim and proper—she's constantly sticking her foot in her mouth—but she is lovable despite her occasionally difficult and overdramatic actions. Watching her is enjoyable even when the film recalls an assembly line of spotty, loosely connected sketches.

As Jack's patient wife Erin, Katie Holmes (2011's "Don't Be Afraid of the Dark") is awfully squandered, given nothing to do but glare disapprovingly at Jack when he makes a snide remark to his sister and comfort Jill when she blows things out of proportion. Does Erin have a profession? Hobbies? Any life at all outside of standing around and supporting her hubby's and sister-in-law's shenanigans? It is hard to say what might have found its way to the chopping block, but this theatrical cut renders Holmes and her character as woefully thankless. In an ensemble filled out with cameos, Al Pacino (2008's "Righteous Kill") gets a sizable—too sizable—part as a hopefully exaggerated version of himself. When he sets his eyes on Jill for the first time at a Lakers game, he instantaneously goes gaga and then won't quit pursuing her. Pacino more than proves he has a sense of humor as he mocks "The Godfather" and "Scarface," but he overstays his welcome and finally turns shrill by the end.

"Jack and Jill" isn't awful or particularly successful. It is, however, the curiosity piece expected, totally undemanding and just bizarre enough in concept to keep one's interest up. In the tale of former "womb-mates" who have drifted apart and learn to appreciate and love each other as adults, there is a certain sweetness to its messages that, regrettably, are downgraded in a misguided climactic scene that has too much going on at once and a reconciliation spoken in gibberish "twin-speak" that completely ruins the emotions involved. Time and again, the film either pushes too hard or opts for the bare minimum when it ought to have been happy to play things more naturally. Adam Sandler's Jill is the standout, no contest, but in "Jack and Jill," she's also basically the only thing on screen worth paying attention to.