The scariest clown movie of 2019 is a documentary.

Nothing’s hiding in the sewers, nobody is bullied and beaten until he becomes Batman’s nemesis.

“Wrinkles the Clown” is about an aged “retired” party clown who offers “behavioral services” to parents. They are clients stretched thin by work and life in a gig economy where social safety nets and family support have eroded, distracted adults who aren’t so much raising their children as looking up from their phones long enough to see how out of control those kids are.

Kids acting out, throwing tantrums, flouting parental authority? Call Wrinkles the Clown to scare the bejesus and Beelzebub out of them.

It started in Naples, Florida, where Wrinkles stickers offering his services papered telephone poles and beach bathroom toilet stalls. A video popped-up on Youtube, showing a clown in a despairing, horrific mask, polka dot jumpsuit and elbow-length rubber gloves, crawling out of a sleeping little girl’s trundle bed on the bedroom’s closed-circuit TV.

Filmmaker Michael Beach Nichols tracks Wrinkles to the van where he works and sometimes “lives” — between nights in the occasional budget motel. He samples Wrinkles’ work, some of it available online.

We’re shown the wave of local, regional and national news coverage that swept the country when this guy with a gimmick first broke out, and get a taste of what being in the middle of a tornadic national phenomenon is like.

He lets us listen in on scores upons scores of calls from reporters, booking agents, and from little kids and alleged adults, asking Wrinkles who he really is, wanting to know if he’s killed children, small kids leaving graphic death threats about what they will do if Wrinkles ever dares to show up to correct their out of control behavior.

“It never ends,” the clown sighs. Here he is, just an old man “living out my last years” in Florida, “trying to contribute something to society” and receiving “multiple death threats a day” from gullible strangers (children, mostly, but not entirely).

“It’s kind of disheartening to hear,” Wrinkles says, his white-bearded face hidden, his voice masked.

Director Nichols interviews a child psychology professor (“Misguided,” he calls Wrinkles, and the people who “hire” him.), the author of a “Bad Clowns” book, a folklorist and others, including a children’s party clown.

“Real clowns aren’t scary,” the happy clown declares, slathering on the greasepaint, as old video of news anchor David Brinkley intoning his intro to the story of the December, 1978 arrest of Chicago clown and mass murder John Wayne Gacy.

But the scariest and yes funniest material in “Wrinkles the Clown” comes from online videos, where parents have let their 10 and 11 year old kids have their own Youtube channel, or concoct a video where a little girl discusses Wrinkles with her discipline-averse Dad, who listens and laughs when she says “I know where the gun is” when the idea of a Wrinkles visit is broached for her bratty behavior.

The film travels to Jonesboro, Georgia and Wytheville, Va., Knoxville, Tennessee to several points in Texas, capturing kids — many entertained by this clown mythology that consumes them, more than a few on the Honey Booboo media and junk food diet.

“I really don’t think of it as ‘child abuse'” one lamentably dim procreator says of Wrinkles and the services he wants provided by him.

The Wrinkles presented here is both a product of groupthink — a myth that enters modern folklore like Bloody Mary and Slenderman (also discussed) — and cultural preconceptions.

Nichols does a ride-along with Wrinkles as he hits the strip club. Because he’s a creepy old loner living in Florida. What else is he going to do?

He’s a cross between “The Simpsons” cynic, Krusty the Klown, and Pennywise — the monster of “It.” Because that’s descriptive shorthand we all understand.

Wrinkles stages and acts-out video horror child-abduction fantasies, complete with a lynch mob in hot pursuit. Law enforcement officials talk about dangers to public safety posed by such figures who incite such mobs.

And then, the copycats sweep the land — pranks and stunts and alleged crimes and hysteria, swept along by CCTV videos all over the Internet.

Fun, fun stuff. And scary? Yes, but not necessarily in the ways you might think going in.

I used to have an editor at a newspaper where I worked who recited her grandmother’s favorite aphorism every time such proof of human manipulation, ignorance, gullibility and cruelty surfaced.

“Fall of Rome,” she’d say. “Fall of Rome.”

MPAA Rating: unrated, with horror images, threats and profanity

Credits: Directed by Michael Beach Nichols, script by Michael Beach Nichols and Christopher K. Walker. A Magnet release.

Running time: 1:18