Oh, to be a snickering 13 year-old boy again, sneaking into the multiplex with other snickering 13 year-old boys to catch “The Happytime Murders” when our parents aren’t paying attention to what we see.

We could hunch down in the seats and watch puppets — Muppets in all but name — have sex, do drugs, get kinky and curse like Samuel L. And we’d laugh and laugh, at the Silly String ejaculate, the “Basic Instinct” puppet leg crossing, at violence — puppets heads exploding in a cloud of fluff, puppets yanked to pieces by dogs.

“Nobody turns my brother into a CHEW toy!”

Because truth be told, sophomoric raunch isn’t funny when you’re older than a sophomore.

Brian Henson, the late Jim Henson’s fiftysomething son, directed this and should have known better, should have been a little classier, should have realized that he didn’t hire a single funny voice to do any of the puppets and that the script didn’t have many laughs, and none that weren’t based on hoped-for shock value.

Not that what we see is all that shocking. Did you see “Scary Movie?” Remember “Fritz the Cat?” Nothing new here, nothing for people (some critics) to “take the vapors” over, anyway.

Melissa McCarthy co-stars as an LAPD detective whose former partner, Phil, a blue puppet voiced and acted by “Muppets” veteran Bill Barretta, has stumbled into a series of puppet killings, former cast members on a beloved old TV show “Happytime.”

Yes, McCarthy co-stars, as this is mostly about the fluff. It’s a world where humans and puppets co-exist, with puppets the objects of endless contempt and rank discrimination.

“All the little dummies wanna do is sing and dance,” the “meatbags” (humans) say. They’re mostly over-sexed, some try to “pass” by having nose-jobs and “bleaching.” Yes, racial stereotyping is the Big Analogy the script clumsily tries to get across. Seriously.

“I have puppet servants at home, and when they get uppity...”

Phil Phillips used to be a cop, kicked off the force for failing to shoot somebody holding Det. Edwards at gunpoint. “He missed on purpose…Puppets won’t shoot other puppets!”

As puppets, who are supposed to be “all fluffy and good on the inside” prove otherwise — addicted to Pixy Stix sugar-fixes, deep into puppet porn, freaky in their sexual practices — die off, Edwards has to re-team with Phil to save the surviving cast members, including their human co-star (Elizabeth Banks, who is game for anything).

Phil has another case he’s working, hired by the pathologically promiscuous puppet Sandra (Dorien Davies). His adoring secretary (Maya Rudolph, playing the funniest character in the picture) cannot quite turn a deaf ear when Phil submits to Sandra’s full-court press.

“I like a little cushion for my cushion!”

I laughed a couple of times, not really at the most outrageous scenes, but at the vintage “Muppets” style sight gags. One puppet has drowned and everybody at the murder scene is advised to look away as “This won’t be pretty.” They wring him out.

It’s not that the concept is too crude, sacrilegious or a blasphemy to Muppet-style puppets. Admit it, when you saw the first “Happytime” trailer or commercial, you laughed.

The actual funny people on the set do their best, especially Banks and Rudolph, wringing laughs out of playing it straight or slinging a funny voice. McCarthy, outrageous as she usually is, isn’t on her game here.

It’s the execution that lets this dog down. Not enough funny lines and even the cheap, dirty laughs are in short supply. They might have broken themselves up on the set, puppeteers finally getting down and dirty and snickering like 13-year-olds themselves. But they’re not funny as these characters, not loose or broad enough in playing these film noir detective thriller archetypes.

There isn’t a Frank Oz or talented, first generation Henson, in the lot.

MPAA Rating: R for strong crude and sexual content and language throughout, and some drug material

Cast: Melissa McCarthy, Elizabeth Banks, Maya Rudolph, Leslie David Baker, Joel McHale and the voices of Bill Barretta, Dorien Davies

Credits:Directed by Brian Henson, script by Todd Berger. An STX  release.

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