You hear the movie’s about a “caveman” cloned to life in modern America, and the jokes pretty much write themselves, right?

You see the image of Will Brittain in Neanderthal makeup and you giggle, maybe just a little.

But “William,” the film that we’re talking about here, is a surprisingly sober and sensitive spin on a subject that’s been spoofed and goofed in everything from “Encino Man” to those “so simple, even a caveman could do it” TV commercials. It’s far fetched and melodramatic, but also thoughtful and touching, every now and then.

It’s a Michael Crichton “Jurassic Park” premise. What if we could bring back a human species that went extinct 40,000 years ago, and has had a bum rap ever since?

That’s what these two doctors — one a charismatic, push-the-envelope paleontologist (Waleed Zuaiter, intense), the other a physician with the sort of credentials that allow her to say “That’s doable” (Maria Dizzia, soulful) — discuss when they meet over drinks.

Dr. Reed (Zuaiter) has a killer Power Point presentation he hits his Wallace U. students with as he introduces them to “Neanderthal Man.”

“Kinda cute, huh? But stupid…a brute. A caveman…short, stocky.”

His thesis? Our “primitive caveman” notions about Neanderthals are “completely wrong.” He makes his case, tracing the bum rap to a racist 19th century scientist who first labeled them that way.

Meeting Dr. Barbara Sullivan (Dizzia) means his far-fetched hopes of “meeting a Neanderthal, face to face” and studying one are within reach. They become “an academic power couple” at the college, “The Neanderthal Project” is born, in secret, and faculty, ethicists and administrators weigh in on “the Mary Shelley-esque” nature of the work.

Not that Dr. Reed and Dr. Sullivan don’t bull straight through, swap egg proteins and DNA and give birth (via Dr. Sullivan) to a baby boy, whom they name William, after the nickname given the specimen who provided the tissue with the DNA that allowed them to do the cloning.

“I thought it was against the law to clone a human,” one faculty member gripes.

“Not in Nevada,” where Sullivan married Reed in an Elvis-impersonator chapel (“Do you promise to never leave Barbara in a ‘Heartbreak Hotel’…and always be her ‘Hunka Hunka Burnin’ Love?”) and where the child was “conceived.”

“William” tells the “research subject’s” story out of order, in a flashback experienced as the young man rides a ferry crossing a sound in the Pacific Northwest.

Mom may marvel at his pre-teen appetite, but to always-clinical Dad, that’s just his
“body mass and metabolism” requiring more protein.

Bullied as a tween (not a good idea) and subjected to endless aptitude and IQ tests all his life, William grows up as a reserved, shy “on the spectrum” type who defies conventional views of what such humans were like.

He speaks plainly and clearly, but has trouble with abstract ideas like “metaphor”  — not that he doesn’t understand them, but because “it feels like something is being taken away from me.”

Director and co-writer Tim Disney (Roy’s son) shows us the kid reading about himself on the Internet, becoming self-aware. But he makes friends, co-stars in the high school musical and endures a pal’s relentless abuse of puns as jokes.

“Didya hear about the stewardess who backed into a propeller? Dis-ASSED-her.”

“That’s so sad.”

“Hey Will, how do fish get high? Sea-Weed! Get it?”

“No.”

We see the rift that opens between his parents and get a hint of the crisis of identity that hits him, as it does many teens — only harder.

Disney carefully steers “William” clear of mockery (“Encino Man” is referenced), even if he has a harder time avoiding the “misunderstood monster” tropes (“King Kong,” “Frankenstein”).

The picture finds touching moments in Will’s rejection by one pretty girl (he looks brutish), but can’t avoid tumbling into Pure Plot Device traps.

It’s a modestly-budgeted affair, which explains its intimate scale, if not its passivity. There’s no media stardom or even media attention for Will, even though his birth was announced with a press conference and great fanfare.

But that suits the picture’s quiet tone and blue mood, complemented by a grey-skied production design.

“William” lacks the fireworks or even high drama that would give it scale or stakes, that would make it more consequential. And its moral parable feels underdeveloped. But Disney still has managed to tell a thought-provoking story on a subject worth viewing through a lens of ethics and morality, even if he can’t quite break free of “Planet of the Apes” parallels.

MPAA Rating: unrated, some profanity, violence

Cast: Will Brittain, Maria Dizzia, Waleed Zuaiter, Susan Park, Beth Grant and Paul Guilfoyle

Credits:Directed by Tim Disney, script by J.T. Allen, Tim Disney. A William Productions/Dada Films release.

Running time: 1:39