I loved the borderlands hitman thriller “Sicario,” and I’m not alone. It has this  meandering but compact narrative, brutal violence meted out by brutish men, the queasy unease it gives you about government sanctioned mayhem and a devilish simplicity underlying all that surface complexity, the thing that drives it.

Revenge.

But while there is still intense pleasure in watching the understated machismo of Benicio Del Toro in the title role (“hitman”) and Josh Brolin as Matt Graver, the off-the-books black-ops guy the government calls in when they need things to “get dirty,” while that tag-team quest narrative is somewhat reprised, I never got got beyond “like” with “Sicario 2,” “Day of the Soldado (Soldier).” And when the thriller’s third act collapses in on itself , breaking its own unsentimental rules and reminding us that this is the studio that reboots “Spider-Man” every three years, whether we ask for it or not, “like” becomes a stretch.

The setting is our still-porous border, where suicide bombers are now sneaking in via Mexico via the cartels that used to make their money bringing us the drugs America craves.

The Islamic terrorists are that “Reicshstag fire” or 9/11 redux so many of us fear — an excuse for a civil liberties/rule of law-flouting government to “get tough” and “go dirty.” That’s what the Secretary of Defense (Matthew Modine) wants out of Garver, a no-holds-barred assault on the cartels that control human smuggling. Start a war between them, don’t leave our fingerprints on it.

The play? Kill a second-in-command here, kidnap a daughter of a kingpin there. That’s how our “Sicario,” Alejandro (Del Toro) comes back on the payroll

That daughter-kidnapping, of an insolent 14 year-old savage, the world-wise Isabel (Isabel Moner), is what goes wrong. That puts our Sicario in the position of protecting her from all comers.

Meanwhile, on the American side of the border, Miguel (Elijah Rodriguez) is a teenager going wrong in McAllen, Texas. He’s signed on with a cousin to become a mule, smuggling Latinos over the Rio Grande. The money, the machismo, the guns and tattoos are too much to pass up.

As in the original “Sicario,” these two threads will intertwine, and not in ways that follow Hollywood conventions.

Two great things from the first film are missing here; the sense of completion and closure, and the pathos brought by having Emily Blunt as a straight-arrow government agent caught up in illegal ops that she, and we, know are sure to lead to blowback. Nobody here is morally conflicted. Nobody here has to have the shenanigans going on hidden from her or explained to her.

Everybody South of the Border is hopelessly corrupt, and the film offers just a glimpse of that sort of stink settling here in the country where we’re supposed to be about “rights” and “rules,” but where the looting and law-flouting is just now getting serious.

Only when things go sideways does the undersecretary in charge (Catherine Keener, great as always) show any sign of second-guessing, and that’s not over morals. She figures this could be cause (another cause) for “impeachment.”

The action beats are perfunctory and director Stefano Sollima never met a drone shot of a truck convoy, a wall of satellite videos from all angles or night vision shots from a chopper, that he didn’t like. SOMEbody read a little too much Tom Clancy, translated into Italian, for his own good. “Surgical strikes” only exist in action movies and Clancy novels.

All I’ll say about the film’s infamous third act is that the picture goes from engrossing to conventional in a flash, and then doubles down on the sort of bottom line “franchise” value that too many studios succumb to these days.

That’s the Marvel Universe we live in at the movies. No story is ever “over,” nothing ever feels complete and satisfying. Everything, even the movies you don’t have to stay all the way through the credits for, is scared to death to leave the viewer wanting “more.”

MPAA Rating: R for strong violence, bloody images, and language

Cast: Benicio Del Toro, Josh Brolin, Catherine Keener, Isabela Moner, Elijah Rodriguez

Credits:Directed by Stefano Sollima, script by Taylor Sheridan. A Sony/Columbia release.

Running time: 2:02