“Honeymoon Crasher” (“Lune de miel avec ma mère”) is a seriously sentimental, seriously tame comedy about a dull guy with risk issues and mommy issues and how he spends his honeymoon.

It’s French (subtitled, or dubbed) and considering the subject, the edge it might have had and the laughs it most certainly does not it’s pretty disappointing.

Honestly, I don’t know why French films advertise this or that star (Julien Frison in this case) as members of the Comédie-Française when they’re parking them in Neflix fare as dull as this.

Frison plays Lucas, a 31 year-old schoolteacher whose wedding to the lovely Elodie (Clara Joly) is interrupted by a cell phone — several cell phones. The ringing is coming from every member of the bride’s posse.

It’s Damien, it turns out. No, not the kid from “The Omen,” but the dashing (Esteban Ocon) and well-traveled motorsport driver.

Not only does opportunistic Elodie take the call (eventually), but when Damien rolls up in a pricy sports car, she flees her wedding and turns poor Lucas into the loser from Ceelo Green’s Greatest Hit.

As our anti-hero has “taken out a loan” for a lavish honeymoon on Mauritius, that’s where he goes. With a little suggestion from Mom (Michèle Laroque from “Ma vie en rose”) and prodding from Dad (Kad Merad), Mom — who never gets vacations — will accompany him to the island paradise.

When the resort’s honeymoon director Gloria (Almodovar discovery Rossy de Palma) lavishes them with a grand suite, there’s nothing for it but to play up the “honeymoon” illusion. Gloria, pursuing a younger man on the hotel staff, sees this younger man/older woman pairing as “inspiring.”

The comically icky possibilities here are many. But aside from Lucas freaking out other honeymooners with tales of how they’ve been together “since birth” (his), little is made of this.

“You wanna give Mommy a hug?”

Potential pratfalls spinning from Mom’s sense of adventure and Lucas’s over-caution don’t fall at all, much less fall flat. A mischievous monkey targets Lucas, and “don’t drink the water” is given the old scatalogical comedy try.

Nothing funny there.

Naturally, there’s a hot adventure staffer (Margot Bancilhon) to tempt Lucas into “forgetting,” and a hunky boat tour sailor (Gilbert Melki) to make Mom fret over the boring marriage she settled into.

The opening wedding turns out to be the best scene, and it falls short.

Cute cast, lovely locations and no comic highlights are the best one can say for this one. There’s “learning,” and even if nobody ever said that was “the best revenge,” it’ll have to do.

Rating: TV-MA, drug abuse, “open marriage” and diarrhea jokes

Cast: Julien Frison, Michèle Laroque, Margot Bancilhon, Kad Merad, Clara Joly, Esteban Ocon, Gilbert Melki and Rossy de Palma

Credits: Directed by Nicolas Cuche, scripted by Laure Hennequart, Laurent Turner and Nicolas Cuche. A Netflix release.

Running time: 1:35