Mix in Monica Bellucci as the Jeffrey Epstein-esque queenpin of a child prostitution ring, Guy Pearce — no stranger to stories about anterograde amnesia — as a mustached FBI agent prone to wearily saying things like “Memory’s a motherfucker,” and pliable source material (the 2003 Belgian thriller “The Alzheimer Case”) that’s enriched by its new setting along Texas’ southern border, and it sounds like the recipe for a solid little programmer. It sounds like the kind of C+ B-movie that’s just good enough to convince you that Neeson still has some skin in the game. “Memory” even boasts a last-minute cameo from America’s sweetheart, Jake Tapper!

Sure enough, the opening sequence alone offers more bang for your buck than the entirety of February’s “Blacklight.” It starts with grizzled hitman Alex Lewis (Neeson) disguising himself as a nurse at a Guadalajara hospital, murdering some young doofus with piano wire while the victim’s intubated mother helplessly watches from her bed, and then fleeing the scene in an Oldsmobile station wagon. It’s fun, it’s brutal, and it’s fully in command of Neeson’s screen image as a homicidal grandpa who’s killed more people than he could ever hope to remember — senile or not. Even more promising is the seemingly unrelated scene that follows on the other side of the Rio Grande, where undercover FBI agent Vincent Serra (Pearce) rescues a preteen Mexican girl from her pimp father by posing as a customer. Serra even pays the girl a visit at the overcrowded detention center to which she’s transferred for deportation, and laments how little the law allows him to do for a child in such desperate need of help. What ties all of these characters together won’t be revealed for a very, very, very long time, but layering their introductions on top of each other seems to anticipate an unusually humane thriller that balances the mental decay of an expert hitman against the moral awakening of a useless fed. Alas, while that is — in broad strokes — what Dario Scardapane’s convoluted screenplay attempts to do, “Memory” is indeed a motherfucker. Not only that, it’s also a perversely generic waste of an intriguing premise, as the failure of this dull and schlocky mess is made all the more frustrating (and bizarre) by the film’s apparent disinterest in Alex’s dementia. Yes, the guy can be forgetful. He’s prone to writing broad instructions for himself on his arm — not quite “shoot person in face,” but close — and at one point he orders an iced tea mere seconds after one is served to him. Alex knows, having watched his brother deteriorate from the same condition, that things are only going to get worse from here, and that motivates him to retire from a business that people only tend to leave in a bodybag.

 And yet, Alex’s failing memory is often dramatized as a more general kind of incompetence; he doesn’t seem like a sick hitman so much as a bad one. He forgets to put the firing pin back into a pistol. He downloads sensitive client information onto a thumb drive. He spectacularly fails to protect a nice sex worker from getting shot in the neck, despite the fact that she spent the night with him for free — even the rusty killer George Clooney’s played in “The American” was able to keep that cliché alive! One genuinely fraught moment, in which Alex mistakenly assumes that he murdered the innocent child whose death is splashed across the local news, isn’t enough to salvage a character whose failing memory is less a poignant source of personal urgency than an occasional trick of narrative convenience. Triggered by his refusal to shoot the same girl who Serra rescues from the clutches of Belluci’s human trafficking operation, Alex’s last-ditch attempt to do something good before he forgets that he can is clear enough in broad strokes, but his terminal case of atonement is handled in such clumsy fashion that even the film seems to grow bored of it. In fact, Alex may not even be the true protagonist of this story, as the jaded Serra — along with his squad of ethically ambiguous underlings, whose dialogue is so wooden that it seems like the actors are grimacing through fresh splinters with every line — gradually finds himself at the center of the action. Although “action” might be too generous a term to describe the film’s sporadic bursts of close-up gunfire. One of them, set in an El Paso parking garage, is cleverly edited to express Alex’s growing confusion; all of them are used to punctuate an endless parade of dramatic scenes in which Serra tries to answer the various questions that Alex’s storyline has already spelled out for the audience (at least Pearce livens things up with a light Texas lilt and a well-earned frustration with America’s immigration laws). The most excitingly choreographed movement in the entire movie is a shot of two golf carts driving past each other at full-speed in the lobby of a corporate tower. There’s a sense that Scardapane is hoping his screenplay’s parallel threads will organically knot into a noose à la “No Country for Old Men,” but it takes an entire hour of turgid setup before Alex and Serra finally cross paths, and the drama only frays apart even further when it tries to pretend these men anything to each other. “Memory is a motherfucker,” Serra reminds us, “and as for justice… it ain’t guaranteed.” But everyone in Campbell’s movie — from the director all the way down to his supporting cast — deserves better than this.

Grade: C-

Open Road Films will release “Memory” in theaters on Friday, April 29.

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