“PEPPERMINT” — 1½ stars — Jennifer Garner, John Gallagher Jr., John Ortiz; R (strong violence and language throughout); in general release

Unless you’re a card-carrying member of the Jennifer Garner Fan Club who is determined to watch every last entry on her IMDB page, there’s no justifiable reason to recommend “Peppermint.”

In Pierre Morel's paper-thin revenge flick, Garner plays Riley North, a soccer-mom-turned-super-assassin who takes on the drug dealer responsible for killing her family.

We briefly meet Riley as she dispatches a bad guy before flashing back five years to her relatively happy existence in Los Angeles with her mechanic husband Chris (Jeff Hephner) and their young daughter Carly (Cailey Fleming). At this point, Riley’s biggest struggle in life is protecting Carly from the unscrupulous wealthy elite kids in her “Firefly Troop” (a stand-in for the Girl Scouts), competing for the best spot to sell cookies in front of the local grocery store and assuring her daughter that to stoop to their level is to lose.

But that sentiment quickly goes out the window when she loses Chris and Carly to a drive-by shooting. It wasn’t a totally random act of violence — Chris was being recruited to rob a local drug kingpin named Diego Garcia (Juan Pablo Raba), and the assassination was punishment by association. But that doesn’t matter much to Riley who, in an unintentionally comic courtroom scene, has to watch the perpetrators walk free thanks to bribes and insider connections.

At this point “Peppermint” — named for the ice cream flavor Carly ordered before her death — returns to the present, where we are supposed to understand that in the ensuing five years, after skipping town with 50 grand of stolen cash, Riley has transformed herself into an elite super-assassin, determined to bring vengeance on anyone connected to her family’s murder.

It would be better to hear that Riley is really some kind of retired ex-CIA operative or that she has at least some kind of military experience to justify her transformation. Something like that would give the film’s absurd premise more of a foundation and might even be a fun nod to longtime fans of Garner’s work as Sydney Bristow on TV’s “Alias.”

There’s an impulse to file “Peppermint” alongside other recent violent, mayhem-soaked “mama bear” movies like “Kidnap,” “Breaking In” or even “Taken,” which, interestingly, Morel also directed. But in those films, the determined parent is offing bad guys in an effort to save his or her child. “Peppermint” is more along the lines of Charles Bronson’s “Death Wish,” delivering vigilante justice in the name of revenge only.

Unlike Morel’s already dark “Taken,” though, “Peppermint” jumps in early and deep into R-rated territory, mixing regular profanity with a generous dose of gunfire, hand-to-hand combat and bloody mayhem. And without a solid story to justify it, too often all the violence feels like simple indulgence.

Justification, in fact, is the biggest thing that “Peppermint” is lacking. With a little more effort in the story department, Morel’s film might have turned into a more competent and engaging thriller.

Instead, “Peppermint” just drives forward like a first-person shooter video game, ignoring opportunities for story development in order to let Riley mow down another round of bad guys in mildly inventive ways. Fortunately for the director, Garner is up for the task, but in the end, even she can’t cover “Peppermint’s” multitude of sins.

“Peppermint” is rated R for strong violence and language throughout; running time: 102 minutes.