So it was a Bond film all along.

All the speculation, the mystery spinning out of the trailers, the hype. And Christopher Nolan gives us his take on James Bond, tailor-made for our perilous times, a bang-on Bond film buddy picture set in Bizarro World.

“Tenet” unfolds like a screenwriting exercise, a time-bending work of back-engineering a plot from its end to its beginning, and then back again. It gives its heroes a simple dilemma — How do you outsmart somebody with access to the future, who can thus predict your every move?

It turns John David Washington into an action hero, Kenneth Branagh into a Russian supervillain and parks Robert Pattinson in an enviable sidekick role, and in skinny boy combat fatigues at one point. Let’s hope he bulks up before donning the Batsuit.

It promises two and a half hours of sitting in a theater, wearing a mask as we listen to Nolan characters try to make themselves heard through their masks. Kind of a thing with him. Dialogue is lost in many a noisy scene — the Bond style “opening gambit” assault on a Ukrainian opera house, the big bang Bond set piece finale, even in a bit of catamaran racing, where the wind and roar of racing foils cutting through the Mediterranean Sea drown out the words.

“Don’t try to understand it. Feel it.”

Awful things are afoot, and a CIA agent (Washington) is brought up to speed after a near death encounter with modern civilization’s irredeemable villains — Russians.

“Inverted” radioactive bullets point to somebody manipulating time, violently altering the present with help from the future.

The hunt for that “somebody” will require access to a lethally inaccessible Indian arms dealer (Dimple Kapadia), a model-gorgeous trophy wife/art appraiser (Elizabeth Debecki), a “free port” airport vault heist and meetings with and threats from the Russian monster who wants to end us all.

Stopping him will require the help of a mysterious British spy (Pattinson trots out a posh accent for that) and mastering the art of “inversion,” a brawl, shootout and car chase that runs backward and forward in time.

It will require a lot of things left unexplained.

“Ignorance is our ammunition.”

The story beats are Bond movie story beats, so there’s more awe at the spectacle than genuine surprise.

“Tenet,” for all its accents, masks and masked dialogue, does manage light touches. Michael Caine’s obligatory appearance isn’t necessary, but is a delight. And Washington and Pattinson click as reluctant “buddies,” even if Nolan never quite takes the picture there.

It’s an ambitious film, but that’s a given with Nolan.

It’s not his best, although perhaps some of that is a product of the extra months of breathless anticipation and speculation.

In the end, we do “feel it” more than we wholly understand it, despite many a pause to explain “the grandfather paradox” of time travel/history changing and the ways the international super rich avoid meddlesome laws and morality imposed on we mere mortals, with their own economy where those who serve them declare “We put no priority above your property.”

We accept Washington — who has screen presence, a wicked side-eye and a deftness in fight scenes, even if the charisma has a ways to go, even if most of his co-stars (Debecki especially) tower over him — as a bonafide action star.

I fretted over Branagh as a Russian heavy. But like Washington, he pulls it off and we accept him in the part.

And we accept that “Tenet” must be seen on the big screen to be truly felt, even if watching at home is the only way we’ll remain “quarantined, and our best chance to really catch (on closed captioning) much of the dialogue.

All this hand-wringing on whether the next James Bond should be female, Asian or Black, and here the thinking film fan’s action sci-fi auteur has shown us the way — Nolan, as always, just ahead of the curve. “Tenet” is as much mind-challenging, action-packed fun as sitting in cinema wearing a mask for two and a half hours can be.

MPAA Rating: PG-13 for intense sequences of violence and action, some suggestive references and brief strong language 

Cast: John David Washington, Robert Pattinson, Elizabeth Debecki, Clémence Poésy, Kenneth Branagh, Michael Caine, Himesh Patel, Aaron Taylor-Johnson, Dimple Kapadia, Martin Donovan

Credits: Written and directed by Christopher Nolan. A Warner Brothers release.

Running time: 2:30