In Hollywood or abroad, there is but one modern immigrant narrative. It’s the horrific story of what someone went through to get “here,” wherever “here” might be.

It’s a rite-of-passage story with built-in pathos and a healthy dose of “Put yourself in their position in their shoes.”

These tales don’t move the needle in the world’s great “human migration” debate. The argument that “They get to come ‘here’ just because they want to” doesn’t wash with many, and that’s the “nice” version of their complaint. Those with empathy, and the self-awareness of realizing their ancestors went through things like this, and that few would put themselves through the often life-threatening ordeals unless they’re facing violence, starvation or deprivation, are already convinced.

So don’t go down the rabbit hole of reading the comments on the IMDb Page of “The Flood.” The more articulate gripes use “propaganda” in their complaints (and most of them haven’t even seen the movie).

“The Flood” is a police procedural version of the immigrant’s odyssey. A crack immigration and naturalization interviewer-interrogator (Lena Headey of “Game of Thrones” and “300”) is sent in to deal with an African man (Ivanno Jeremiah of TV’s “Humans”) whose second act on British soil — after paying to be smuggled in illegally — was to jump the cops who rousted him from the back of that lorry freshly-arrived from the continent.

Her boss (Iain Glenn of “Game of Thrones”) is pressuring her “to get him out of here before the election,” pressure that’s coming “from above.” She’s got other pressures at home. So she’s all business, ticking off a long list of questions that decide if this man is sent “home” to Eritrea, one of the world’s most dangerous conflict zones.

“Where did you arrive in Europe? Can you briefly say why you cannot be returned?”

The answer to that — “They will kill me.” — leaves her unmoved.

“Everyone’s got a story,” she says. “Wendy” has heard it all.

“Oh, you’re name is Wendy? That”s my mother’s name!”

“That’s a new one!” the boss chortles.

What follows is an intimate drama detailing that interrogation, many many questions, with the subject, “Haile,” trying to find humanity and common ground with his interrogator and Wendy doing her damnedest to not let that happen.

In flashbacks, we see Haile’s story, or his version of it. A failing of “The Flood” is never allowing any doubt to enter the viewer’s mind (thus putting us in Wendy’s shoes) as we hear of war, war crimes, torture and escape.

“You ran across the border?”

“I crossed the border,” Haile says, without bluntly reminding her he just finished saying he was beaten on the soles of his feet. “I could not run.”

The flashbacks show us that escape, the perilous boat journey across the Mediterranean, the harrowing arrival on shore and the ugliness of “The Jungle,” the migrant camp on the French coast where cops are the lesser of every immigrant’s fears. The real predators are their peers.

As he relates these stories, Haile tells who he threw in with — pregnant Reema (Mandip Gill) and her husband Faiz (Peter Singh).  And we and Wendy start to see his arrival in a new light.

It’s a story that’s more grounded and sturdy than moving. Headey doesn’t give us much to cling to here, fending off phone calls hinting at the trouble at home, having her boss stare literally over her shoulder as she asks questions — poker-faced, piecing together the puzzle, probing for the truth.

Jeremiah has the showier part, a man scarred by what he’s been through, traumatized, but trying to charm and pass himself off as “not dangerous,” even though he “attacked” a police officer.

Everything in his life has come down to “negotiation,” no matter what Wendy says about their exchange. How much can he tell her? What will she believe?

There’s an earnest “humane side of history” that feels like it’s in play when actors take roles in films like this. It’s an act of courage, considering Britain’s anti-immigrant climate. And the unfortunate plot detail that Faiz has a nasty cough helps make the “Kick him/kick them all out” argument, to some.

But the flashbacks, the “everybody has a story” part of “The Flood,” puts it over. Even the hardest heart — Wendy’s included — has to be willing to hear such stories if we’re not to betray every single thing countries built on the rule of law and hard-won reputations for being civilized and humane aren’t to be abandoned.

And on the other side, recognizing that not every “story” is as worthy, that not every entry should be a foregone conclusion, might help in defusing the growing crisis of our times, not if those of us on the receiving end don’t want to be inundated by “The Flood.”

MPAA Rating: unrated, violence

Cast: Lena Headey, Ivanno Jeremiah, Mandip Gill, Peter Singh and Iain Glen

Credits: Directed by Anthony Woodley, script by Helen Kingston. A Samuel Goldwyn release.

Running time: 1:39