It isn’t often that a documentary lumped under the general “nature film” label fundamentally changes our view of an animal, its environment and the natural world. I doubt many of those who labor in this science museum/ BBC/ “Nature” and Discovery Channel corner of the cinema harbor such expectations for their work.

But the gorgeous and almost shockingly moving “My Octopus Teacher” does just that, something that sets it so far above its genre that it might very well be the Oscar favorite for Best Documentary, judging from its many other awards.

South African cinematographer Craig Foster narrates the film and describes the burnout he was going through prior to taking his camera into the waters off the western Cape of Storms in his homeland. His prior work was almost entirely in the bush among the hunting cultures of Africa, and like all such films, required years of commitment and embedding and labor.

But snorkeling off the coast in “some of the wildest, most scary places to swim on the planet” gave him hints of that hunter’s cunning in the small, wonderfully-camouflaged octopus — the tracking, tricks, disguises and tactics it uses to hunt prey or avoid the “pyjama sharks” that are its primary predator. And as there’s precious little research of octopi in the wild, he set out to film an octopus “every day” for months on end and see what he’d learn.

He sees it as “a liquid animal,” and marvels at its ability to pick up shells and cover itself in them — dozens at times — to hide from prey or predators. It’s “an animal that has spent millions of years learning how to be impossible to find.”

And as “she” gets familiar with his non-threatening presence, they make a connection. Even recent decades of news accounts of octopi showing off their smarts in the world’s big aquariums didn’t prepare him, or us, for that.

“A mollusk shouldn’t be this intelligent.”

Foster returns to the sea for hundreds of days and learns to “track” the octopus via the snail, crab and lobster shells it leaves behind after meals. He watches it reason through strategies in how to track and trap such creatures and sees its life-and-death struggle to avoid the long, cunning pyjama sharks.

And he breaks the human/animal barrier, getting close, letting the octopus check him out. He asks the question we want to ask at the moment we decide its worth asking.

“What is the octopus getting out of this” interaction?

His answer surprises us and upends some of the science on these “alien” creatures that seem a lot smarter and more social, despite their solitary existence, than anybody knew.

“My Octopus Teacher” has some of the most stunning underwater footage — of the churning kelp forest under the seas of the Western Cape — ever filmed.

If they gave out Oscars for degree of difficulty, this film would be a shoo-in. Even the equally enlightening and uplifting “Crip Camp” wouldn’t stand a chance by that yardstick. If you’ve ever snorkeled, you know how impossible getting all this footage between gulps of breath must have been.

Thankfully for us, Foster has the lungs, the eye and the heart to stick with this story, to tell it and to change the way we look at the natural world, all through the lessons of an octopus.

MPA Rating: TV-G

Cast: Craig Foster, Tom Foster.

Credits: Scripted and directed by Pippa Ehrlich, James Reed. A Netflix release.

Running time: 1:25