“Lust Life Love” sets out to be a “Polyamorous Sex in the City” with a lot more sex, a bit less glamour and no fun at all.

Writer, co-director and star Stephanie Sellars takes a shot at lifting her acting career and writing career out of short films with a movie inspired by her short-lived “Lust Life” column in a now defunct free weekly in New York back in 2006-7. But when you’re focused on sex and romance as a topic and narrating, in voice-over, your column (a blog, here), you can’t help but invite comparisons to Sarah Jessica Parker and Kim Catrall’s finest hours.

Veronica (Sellars) ponders the polyamorous imponderables on her popular blog. She wants to know “Is true love a reason to be monogamous?” She wonders if “three people can come together in mutual desire and not fall apart.”

Anybody who has ever seen a screen romance or rom-com on TV or film knows the answer. But as the old joke goes, every generation has to announce its reinventing sex, romance, family, child-rearing or what have you. And whether its “Harry Met Sally” or “Friends” or “thirtysomething” or “Sex and the City,” the “Eureka!” moment comes when they realize they haven’t reinvented anything.

So “Lust Life Love” puts the polyamory fad — if indeed one can call it that — out there and in the spotlight. Veronica, who identifies as bisexual, juggles her pierced and tattooed girlfriend (Jeanna Han) with this hunky young Latino artist (Rolando Chusan) she poses for, and beds on occasion.

And then there are the others she picks up — solicits, etc. — and uses as fodder for her column. The opening scene of “Lust Life Love” is her sharing lust with a couple she’s just met.
They’re the first people she uses the phrase, “no pressure, no expectations” with.

But we quickly figure out, through her repeated usage (and the fact that others in her “world” use it), that it’s their version of “just kidding.” Of course there’s pressure. And it’s all about “expectations.”

Veronica’s life, as a character, revolves around sex — sex parties (orgies), casual pick-ups, flirtations that don’t stop when she learns this new fellow Daniel (Jake Choi) is married.

Veronica may play semantics games with “swingers” and “key parties,” something her parents (Susanna Fraser and Bill Irwin) joke about from “back in OUR day.” But we, like they, see through her kidding-herself BS.

As she and a third person (Makeda Declet) form the “not a couple, a triad” that finishes off Daniel’s marriage, we can see the red flags, the lie in her “It is enlightening to see my partner through the desires of another.” Somebody’s about to get jealous.

“Lust Life Love” makes Veronica her new beau Daniel’s tour guide into this world of alleged “heartbreak insurance,” “the advantage” seen in a sexual/romantic arrangement that allegedly doesn’t leave one shattered if one person in the “triad” breaks things off.

The “parties” may be masked or unmasked, they’re still orgies. The club “Chemistry” where they sometimes meet their hookups and longer-term relationships isn’t labeled “a sex club.” But a generation older than these hipsters sees them for what they are.

Are they not teaching kids about the ’70s in school? At all?

Her mother remembers. She wonders why her daughter doesn’t write children’s books. But a fan who recognizes her on the street asks an even more insulting question.

“Have you ever considered porn?” “No,” she snaps. “Have you?”

Still, when the notorious blog gets the attention of video website producers, Veronica’s dismissal of “sex workers” seems premature. She’s staging “parties,” hook-ups and coupling (tripling) for the camera.

But when you’re wading into all this like you’re the first person to ever dabble in something your generation merely added a new name to, “self-knowledge” is just one of many “knowledges” you lack.

Sellars puts it all out there in this film, and comes off as competent both as an actress and screenwriter. It’s the gap between “competent” and “compelling” that trips her up.

The many sex scenes in “Lust Life Love” scream “INSECURITY,” as in there’s no confidence in either the scripted interior lives of the characters or the cast’s performance of them. When you limit your story to just “Lust” and “Love,” the life you depict can’t help but seem shallow and contrived.

Rating: unrated, sexually explicit, profanity

Cast: Stephanie Sellars, Jake Choi, Makeda Declet, Jeanna Han, Rolando Chusan, Susanna Fraser and Bill Irwin.

Credits: Directed by Benjamin Feuer and Stephanie Sellars, scripted by Stephanie Sellars. A 1091 release.

Running time: 1:36