In the sixteen years since the release of 1998's "The Wedding Singer," there have been few, if any, onscreen romantic couplings with the irresistible chemistry that Adam Sandler (2013's "Grown Ups 2") and Drew Barrymore (2012's "Big Miracle") shared. Watching them together was akin to witnessing magic take place, and it helped that the film—a 1985-set comedy with heart, buoyancy and a happening soundtrack—proved as effortlessly likable and ultimately touching as the actors themselves. In 2004, Sandler and Barrymore paired again in "50 First Dates," and still had that special something that cannot be faked once two people are thrown in front a camera and expected to make sparks fly. Ten years later, their third film, "Blended," is the opposite of a charm. They remain plenty charismatic when sharing the same frame, but the touch-and-go script by Ivan Menchell and Clare Sera lets them down. Director Frank Coraci (2012's "Here Comes the Boom"), who injected such energetic pacing into "The Wedding Singer," gives this particular story a curious, overcrowded sluggishness.

When their disastrous blind date to Hooters starts bad and gets worse, Dick's Sporting Goods manager Jim Friedman (Adam Sandler) and professional closet organizer Lauren Reynolds (Drew Barrymore) expect to never see each other again. He is a recently widowed father raising three daughters, she is a divorced mother with two sons, and neither of them are quite in the right headspace to open themselves to a new committed relationship. Through a series of chance events, both families end up at the same lavish resort destination in Africa over spring break. Jim and Lauren do not mesh well at first, but as they get to know each other and their respective kids they start to find a common ground on which they can relate. It might not have been love at first sight, but both are wise enough to realize the most meaningful bonds in life are built from more than just fantasy sentiment.

Adam Sandler and Drew Barrymore clearly have a field day working as co-stars, and, per the recent norm for Sandler, he has ensured that the plot takes him and the rest of his cast to an exotic vacation spot. The trouble with "Blended" is that the parts never quite, well, blend. The picture has its moments, from Lauren accidentally calling Jim's middle daughter, Espn (Emma Fuhrmann), "C-SPAN," to a set-piece where Lauren gets into a precarious position while parachuting during a safari, but even some of the funny parts don't quite stick the landing following promising setups. Meanwhile, lame physical gags involving ostrich rides, fake crocodiles and humping rhinoceroses go nowhere. The recurring appearance of an over-the-top troubadour (Terry Crews) who pops up throughout the trip (and even after they have returned to the U.S.) is involved in one or two amusing sight gags, but serves no purpose and otherwise falls flat.

The proceedings start looking up in the second hour as Jim and Lauren soften and start spending more time together, attending a couples massage class and sharing a private dinner served by a wait staff of monkeys. As they discover that they aren't very different at all when it comes to their views on parenting and the importance of their children, the old winning magnetism of seeing Sandler and Barrymore collaborate on a film comes rushing back. If anything, there isn't enough of just the two of them as an exorbitant amount of other characters fight for screen time. Bella Thorne (of the 2010-2013 Disney Channel series "Shake It Up!") is radiant as Jim's tomboyish eldest daughter, Hilary, who keeps getting mistaken for the opposite sex before a requisite makeover reveals a knockout young lady underneath. That she only attracts fellow teenage tourist Jake (Zak Henri) after she gets hair extensions and a dress sends a questionable message, but Thorne is excellent with what she has to do. There also is the aforementioned Espn (named after Jim's favorite television channel), who treats her dead mother like an imaginary friend; youngest daughter Lou (Alyvia Alyn Lind), whose precociousness is offset by her fascination with demonic voices; Lauren's sons Brendan (Braxton Beckham), currently going through puberty, and Tyler (Kyle Red Silverstein), a Little Leaguer prone to losing his cool; Jake's father, Eddy (Kevin Nealon), and his dad's much younger new wife, the shimmy-loving Ginger (Jessica Lowe); Lauren's unreliable ex-husband, Mark (Joel McHale), and Lauren's best friend and work partner, the brassy Jen (Wendi McLendon-Covey). It is a lot to juggle, and there are more players where those came from.

"The Wedding Singer" was such a rousing success on all fronts that perhaps the downside is that Adam Sandler and Drew Barrymore will never quite be able to match it with future projects. Still, one comes to expect a little more effort than what "Blended" provides, as the film often feels like an inferior, more slapdash variation on 2011's Hawaii-located "Just Go with It." Running jokes about Jim's weight—he is described as everything from "fatty" to "chubby loser"—are (1) lame and (2) nonsensical, since he is entirely normal-sized, while a cameo from Alexis Arquette (2005's "Lords of Dogtown"), again behind a keyboard, is wasted, only serving to remind how much of a lesser movie this is than "The Wedding Singer." Too many misunderstandings in the homestretch serve to drag the inevitable out rather than build suspense. Meanwhile, Wendi McLendon-Covey (2011's "Bridesmaids") is never not a welcome presence—her hilarious (and hilariously touching) performance on TV's "The Goldbergs" is nothing short of brilliant—but her spry turn as Jen is relatively small and should have been expanded in exchange for excising some of the more extraneous side characters. All things considered, "Blended" deserves to be faster, funnier, peppier and less cluttered than it is. It is a testament to Sandler and especially the forever lovely Barrymore that even in lesser cinematic larks, they escape unscathed. Next time—and hopefully there will be a next time—they will look a little harder for the perfect screenplay worthy of their collective effervescent appeal.