Folksy Midwestern culotte culture comes to sunny, silly Florida in “Barb & Star Go to Vista Del Mar,” a not-quite-romp cooked up by “Bridesmaids” breakout Kristen Wiig and the actress-screenwriter who scripted that breakout hit, Annie Mumolo.

It’s like a “Saturday Night Live” sketch given a lot of money so that they could hire every showbiz pal they have as they tried to fill 107 minutes of screen time.

Say this for Wiig and Mumolo, who co-wrote this. Whatever points they score against Nebraska in the opening scenes, there’s eerily-amusing accuracy to their (dated) take on the Sunshine State. The salmon and teal, canary yellows, lilac to lavender Disneycolor palette, the fruity cocktails and tourists, the Jimmy Buffett and uh, Bertie Higgins on the soundtrack? Nailed it.

Sure, they had to go to Mexico (Cancún) to mimic the Florida of tourist lore, but whatever works.

Divorced and widowed Barb (Mumolo) and Star (Wiig) are Nebraska furniture saleswomen joined at the hip and the lip. They do everything together, including discouraging customers who might want to buy the sofa they enjoy sitting on together at the store, chattering away.

Their voices are high and Midwestern nasal, and each’s inane banter tumbles over the other’s — a dialogue/duologue that ponders the Big Questions of life.

“It’s odd to think that all the raccoons in the world are sleeping right now.”

Say what?

“Listen, I don’t really know more than I’ve already said. And some of what I said I’m even sure I actually know.”

When the store shuts down and they’re tossed out of their authoritarian “Talking Club” (Phyllis Smith of “The Office” is in it, “SNL’s” Vanessa Bayer plays the martinet who rules it with an iron first), the “girls” have to admit “We’ve lost our shimmer!”

Barb would like to see her friend “get out there.”

Star? “Men find me disgusting, and I’m OK with it.”

But a pal (Wendy McClendon-Covey of “The Goldbergs”) goes on and on about this resort she just visited on the coast of Florida. Barb & Star decide on a vacation.

They’ll go, soak up the sun, sip “boat drinks,” ride the banana boat and maybe meet someone. Greeted by a Disney Deco dazzling and amusing production number on arrival, they’re gobsmacked and you can’t help but get your hopes up that “Barb & Star” have found their shimmer, and the movie has found its voice.

There’s even a singer-pianist (Mark Jonathan Davis) who is just killing it in the lounge with a tune of his own invention (actually, Wiig co-wrote it).

“I love boobies. I love gazongas. I love knockers and chimichangas!“

But this is where the Supervillain plot settles in and the movie, waterlogged already, all but sinks.

The supervillain (Wiig in a second role, in Kibuki pancake makeup and alien-blue contacts) has a bone to pick with this town, a diabolical plot to destroy it and a lovesick minion (Jamie Dornan) she’s sent to seal its fate.

Dornan, the once-and-always Christian Grey of “Fifty Shades of” You-Know-Who, is the surprise delight in the casting here. His secret agent character, Edgar Pagét, gets swept up in Barb & Star’s company, gets drunk and into a compromising position with them. Next thing you know, he’s singing and dancing about this new love he’s found.

Christian Grey, singing and dancing. A lot of ladies would pay to see that, right? But that’s the lone highlight of the last two thirds of this lighthearted but heavy-handed farce.

It’s the sort of film that defines “culottes” as an opening credit, and tries to wring laughs out of “hot dog soup” (the gals’ Midwestern specialty), the goofy stuff the ladies pack, the way they apply sunscreen and Damon Wayans Jr.

Wayans, the least funny member of that extended family, is on the cusp of amusing here, as a hapless second agent sent to assist the first.

Another of The Lady’s henchmen is little Yoyo (Reyn Doi), a kid whose cover is as a paper boy who loves singing along to Streisand.

There might be enough here to make this comedy zip by. Wiig can be hilarious, and there are two of her here. And Mumolo didn’t just script “Bridesmaids,” she’s had supporting parts in many a comedy from “The Boss” to “Bad Moms.”

But entrusting this to a first-time feature director with episodic TV and showbiz documentaries dominating his resume proves unfortunate. The funny bits drift past their payoff, the pace flags (88 minute movie stretched out to 107) and the light, tongue-in-cheek tone, the riffing banter between the leads isn’t enough to save it.

Worst of all, they only gave Dornan one quite-funny number, and neither Wiig nor Mumolo have a movie moment that’s up to that.

MPA Rating:PG-13 for crude sexual content, drug use and some strong language 

Cast: Kristen Wiig, Annie Mumolo, Jamie Dornan, Damon Wayons Jr. and Wendy McClendon-Covey,

Credits: Directed by Josh Greenbaum, script by Annie Mumolo and Kristen Wiig. A Lionsgate release.

Running time: 1:47