TRIBECA: A traditional romcom from the outside that takes some emotionally honest turns for the better, Tribeca dramedy, “The Boy Downstairs” sports a trivial veneer that eventually reveal poignant insides from a refreshing female perspective. But it’s certainly not without its flaws.

Built on credulity-straining contrivances this machination mars a familiar, but engaging story about boy meets girl heartbreak. However, the strong performance by Zosia Mamet (“Girls”) generally carries the film through its patchy moments. Uneven in shape, overall, as a directorial debut it still shows a lot of promise.

Boy_Downstairs_Zosia Mamet

The main “hook” however, is a cloying conceit of coincidence that belongs in the glib romcom half of the movie, not the earnest moving picture it transforms into. Diana (Mamet) returns from London to the U.S. after a four-year trip abroad. Starting from scratch, she embarks on a monumentally challenging mission—finding a decent and affordable apartment in New York. Eventually landing a little gem in Brooklyn, plus a convenient bff landlord who lives upstairs to go with it (Deirdre O’Connell), starting life anew doesn’t seem so daunting. That is until one major hiccup arises: the boyfriend whose heart she broke when she left the country way back when (Matthew Shear) happens to live in the same Brownstone downstairs (cue a mild groan).

The awkward proximity to her ex, Ben (Shear) reopens old wounds and forces Diana to reflect on a burgeoning relationship that ended abruptly before it had the chance to fully blossom.

But what begins as a lightweight, run-of-the-mill situational romantic comedy eventually develops into something more mature. “The Boy Downstairs” achieves this through thoughtful, well edited flashbacks. Traveling back in time the movie gracefully cross cutting between the ghosts of this relationship past and the present where Diana tries to navigate the trickiness of living next door to her old beau.

The filmmaking debut of writer/director Sophie Brooks, her writing in and use of flashbacks are effortlessly crafted, uses sensory memory like recall as an expressive way to communicate the sweet and nostalgic touchstones of the relationship.

Clearly centered on first love, or at least the first significant love, “The Boy Downstairs” carries a lot of moving affection, nostalgia and regret for the past while trying to forge ahead with the future—anyone who’s ever felt wistful for a relationship that never fulfilled its potential will relate. But its ending, which doesn’t feel totally earned given Diana’s character arc, plays out a little bit like the director’s wish fulfillment.

The Boy Downstairs Matthew Shear

But Mamet shines and demonstrates a surprisingly strong range far beyond the entertaining, but sometimes cartoonish character she played on “Girls.” Not quite on par with exceptional performance, Matthew Shear still holds his own as the poor boyfriend shmuck unintentionally toyed with by Diana.

Frustrating to watch at times (no one likes to watch the heart get kicked around), but authentic, one of Brooks’ best observations is that of the flighty 20-something that doesn’t know what her or she wants. And it’s more complicated than a fear of commitment (though perhaps that’s mixed in the emotional stew as well). Diana clearly loves Ben, but is afraid and unsure if she is worthy of his bear-hug adoring love because her side eye is focused on her future and career. Uncertainty, selfishness and mistakes made create a toxicity that any ex-lover would resent. It’s this complex consideration of the heart where “The Boy Downstairs” earns its highest marks.

Truthful brokenhearted movies told from a female point of view are pretty damn rare (“Goodbye First Love” comes to mind). And the reverse of say, “(500) Days Of Summer” feels equally scarce too, so it’s in a way, very invigorating to receive this fresh and underseen outlook on screen.

An earnest examination of love, heartache and the tumultuous time of 20-something not-quite-there adulthood, “The Boy Downstairs” straddles a patchy line between comedy and drama with mixed results, but when all is said and done, the auspicious film acts like a mature consideration of the scariness of vulnerability and laying your heart on the line. [B]

Follow along with all our coverage of the 2017 Tribeca Film Festival.