Tribeca Film "Rubberneck"

Alex Karpovsky is a man of considerable talent whose time has come. Lost in the hype of the so-called mumblecore movement when it first erupted out of the SXSW scene, Karpovsky was not as prolific or media-savvy as Joe Swanberg or the Duplass brothers, but his interests as both actor and filmmaker have more complex ingredients.

Over the last five years, Karpovsky has made a mockumentary about bird watching ("Woodpecker"), a real documentary about improvisation ("Trust Us, This is All Made Up"), and now a tense thriller, "Rubberneck," in which he also stars. He has additionally acted, usually in comically discomfiting roles, including Andrew Bujalski's "Beeswax," Bryan Poyser's "Lovers Hate," and Lena Dunham's "Tiny Furniture," as well as several other bit parts. He's in fine form in "Supporting Characters," once again teetering on the edge of sarcasm and emotional fragility, and always the most interesting person in the room. (On Dunham's HBO show "Girls," he's as vocal as any of the prominent female castmembers.)

Karpovsky's two appearances in movies at the Tribeca Film Festival this year, in one case as actor and in another as actor-director, provide a unique opportunity to analyze his broad range. In "Rubberneck," Karpovsky plays a lovesick Boston lab technician slowly losing his mind, while "Supporting Characters" has him as a struggling New York film editor grappling with a failing relationship.

He's in fine, familiar form in "Supporting Characters," but "Rubberneck" takes him outside his safety zone. Karpovsky's shy demeanor often clashes with his self-effacing ramblings to amusingly ironic effect. He's still a headcase in "Rubberneck," but has reigned in the neuroses, burying them in the texture of his compelling new drama. Using elements of a real story and running with them, Karpovsky plays lonely bachelor Paul, whose introverted ways begin to evolve after a sensual weekend tryst with a lab partner whom he can't stop fawning over.

As the movie burrows deeper into Paul's psyche, his claustrophobic mindset dominates through an appreciably eerie score and carefully arranged camera angles that generate a noticeable sense of remove. The drab laboratory setting enhances Paul's need to escape from his inner demons, the full extent of which only emerge in the final act.