“A Simple Favor” is a thriller that ticks likes a Timex, a precision exercise in button-pushing manipulation and a laugh out loud mystery that mocks its own manipulations, giggles at its own far-fetched twists.

Paul Feig of “Bridesmaids,” working from a  Jessica Sharzer (“American Horror Story”) script based on the Darcey Bell novel, gifts us with a goof on “Gone Girl, a calculating dark comedy that skips by on the ,most on-the-nose casting of the fall.

Blake Lively as the willowy, brassy and profanely sexy mom-gone-missing, and Anna Kendrick as the Mommy Vlogger/Mini Martha Stewart who is her brand new best friend — how perfect is that?

Stephanie (Kendrick) is the demure, over-eager, overdoes it Single Mom/SuperMom at their kids’ suburban Connecticut school. Emily is the rich, high powered PR director for a famous fashion designer in the city. They meet, and it’s love at first sight. Their little boys want a play date.

“Mommy already has a playdate…with a symphony of anti-depressants!”

Emily jokes about the kids drinking, drops F-bombs like she buys them wholesale, and from the tip of stilettos to the top of her perfectly-coifed blonde tresses, is everything Stephanie is not. “Love” doesn’t begin to cover it.

Within minutes, Emily is schooling Stephanie to stop apologizing reflexively, “a f—-d up female habit,” how to confront powerful men head-on, how to make the perfect London martini and she’s bucked up her non-existent libido with a bubbly, “Baby, you’re too sexy to give up!”

Within hours, they’re sharing, and then over-sharing — “secrets.” Stephanie’s are…interesting. Emily’s have to do with her once-promising writer-husband, played by Henry Golding with all the sexual sizzle he lacked in “Crazy Rich Asians.” Stephanie’s crack, that they have “more chemistry than a science fair” is right on the mark.

And within days Stephanie is being asked to pick up the kids, watch the kids, all leading up to the day Emily just vanishes. Stephanie must deal with two boys that have been dumped on her, a worried best-friend’s husband who leans on her, cops who wonder just what’s going on and a rising suspicion that Emily isn’t missing, she’s split, that she isn’t dead but just “gone.”

Kendrick carries off the cuteness with her usual pitch perfect timing and physically expressive acting. Stephanie is awkward, from her mask-the-fear smile to her Mom dancing to Emily’s vintage French pop, and guilty stumbling rummage through Emily’s closet.

There’s too much cuteness, of course. But the whole Mommy vlogger element makes a convenient plot device when Stephanie starts crowd sourcing the search for Emily. And if anybody can pull off a saintly-sweet but R-rated Nancy Drew, it’s Anna K.

“Every mom knows,” she says of her amateur sleuthing, “if you want something done right, do it yourself.”

Lively is so much more than a clothes horse in movies like this and “The Age of Adeline,” films where she’s “an enigma,” a woman with a secret. She is stunning, brazen, blunt and scary, and she turns Emily into an irresistible hormonal force — a man-eater/woman-teaser who turns every scene into “The Shallows” with her as the shark.

Feig’s touch is most pronounced on the picture’s periphery, the bitchy coterie of moms whose queen is the bitchiest of them all, a gay parent (Andrew Rannells), smart alec cops (Bashir Salahuddin), foul-mouthed kids and a fashion designer (Rupert Friend, never more hilarious) whose PR director may be missing, but that doesn’t mean he won’t insult every inch of your wardrobe in between your questions.

A favorite cut, the mean moms notice Stephanie’s methodical search, her helpfulness with Emily’s family and their queen snips, “It’s an arts and crafts project” to her.

The picture delivers one scene of shocking violence, and a third act full of twists that are pure hokum.

But Feig plays his audience — especially the female two thirds of it who will laugh, reel and grab hold of the empowerment (good and evil) messages — like a Wurlizter, the kind that used to accompany silent film melodramas where the vamps were just as obvious, the heroines just as pure (seeming) and the twists just as laughable and simple as “A Simple Favor.”

MPAA Rating: R for sexual content and language throughout, some graphic nude images, drug use and violence

Cast: Anna Kendrick, Blake Lively, Henry Golding

Credits:Directed by Paul Feig , script by Jessica Sharzer, based on the Darcey Bell novel. Lionsgate release.

Running time: 1:57