“The Other Laurens” is a slow, drifting mystery thriller that takes a while to decide what it’s about, takes another while to add on complications and adds a third while to attempt to get to some sort ofint.

The Belgian director and co-writer Claude Schmitz (the thriller “Carwash” was his) doesn’t appear to know the word “pacing” in Flemish, Walloon, or any of the three languages that turn up in “L’autre Laurens” — French, Spanish or English. His 117 minute movie has maybe 70 minutes worth of incidents, characters and action in it.

Gabriel Laurens, played by Olivier Rabourdin of the “Taken” movies, and Woody Allen’s “Midnight in Paris,” is a 50ish frump, a Brussels detective (“The perferred term is ‘private investigator.”) who would never earn a second glance in a crowd. He does surveillance, “background checks” he calls it, to catch cheating spouses.

When we meet him, he’s dealing with the loss of a sibling and the impending death of his aged mother. Her passing throws his dull, myopic life into a crisis. Gabriel’s rich brother François was taking care of her bills, and had fallen ruinously behind.

Then that dead brother’s teen daughter Jade (Louise Leroy) shows up at his doorstep. Her suggestion that maybe Dad didn’t die in an accident and the fact that Gabriel is broke sends them south, driving her back to The White House, the spacious French mock-up of the U.S. executive mansion she grew up in outside of Perpignan in the South of France, close to the Spanish border.

It’s a rough and tumble border region where Spanish thugs and French hustlers and bike gangs still do a brisk business, EU be damned. What was François mixed up in?

Did I mention that he and Gabriel were twins? That, as you might expect, leads to some confusion and perhaps even deadly complications. Because the dead man’s American widow (Kate Moran) is, one and all agree, “not to be trusted.” And her biker-gang minions, one of whom tails Jade around on a motorcycle, are not the sort of people she or Jade or Gabriel or even the testy, wary Spaniards should consider crossing.

Truth be told, there’s enough going on here, enough mystery to the death and sketchy dealings of the widow, the Spaniards and French bikers to hold one’s interest.

Rabourdin makes a fine anti-hero, looking anything but heroic or even a guy who ever considered hitting a gym. He’s playing the twin always overshadowed by his sibling, always shortchanged and cheated by pushier François.

Gabriel’s story arc will match his “detective” skills against oddball local cops, the latest wife, a mistress with Spanish mob connections and growing-up-too-fast-and-loose Jade.

All of which sounds “in over his head” promising. But Schmitz moves all this along at a caterpillar-in-fresh-frost pace, which dulls the mystery and blunts the action that sort of floats by mostly in scattered moments in the third act.

By the time our tale takes its turn towards the BIG (not that big) finish, our director has squandered much of our interest and most of the viewer’s goodwill.

Rating: unrated, violence

Cast: Olivier Rabourdin, Louise Leroy, Kate Moran, Marc Barbé and Edwin Gaffney

Credits: Directed by Claude Schmitz, scripted by Claude Schmitz and Kostia Testut. A Yellow Veil release.

Running time: 1:57