“You’ve got to promise me things won’t get weird,” Tabby (Diana Bang) tells her neighbor Ben (Thomas Middleditch), knowing he can’t make any such assurances in “Entanglement.” He’s just asked her if she can help him find a woman who was slated to be his sister around the time he was born, having been told by his father just after a heart attack that her adoption would’ve gone through if he hadn’t been conceived and having recently read up on parallel universes and quantum physics, he’s eager to find out what could’ve been. He also is clearly missing something in his life, introduced by way of a series of botched suicide attempts that like everything else for Ben have a meticulous plan behind them before not quite working out the way he thought they would.

Things go much better for writer Jason Filiatrault and director Jason James in pulling off the accurately titled “Entanglement,” a bittersweet comedy that aims to go deeper than even the gutteral laughs it inspires and largely succeeds. Resting lightly on the shoulders of Middleditch, who parlays the raw nerve energy he displays week in and out as the beleaguered tech genius on “Silicon Valley” into a slightly sad, soulful performance as Ben, the film follows him out of the twin traumas of nearly seeing his father die after trying to kill himself by finding his almost sis Hanna (Jess Weixler) – or it could be argued she finds him, insisting he take her number at a pharmacy before he’s aware of who she actually is. While this fits in neatly into Ben’s ideas about how events are arranged by the universe, any reasonable audience member might think it’s a little too convenient, as does Tabby, who believes Hanna might be catfishing him.

The credibility gap is where “Entanglement” gets interesting as one can see Ben and Hanna complete together like puzzle pieces, but from completely different sets and their encounters grow more surreal. A late-night dip into the local swimming pool surrounds the pair with jellyfish and one can see Ben’s mind start to wander as his reflection in the mirror starts talking back to him, all evidence that despite all the exuberance the vivacious Hanna has brought him, he has no peace of mind. In the hands of less sensitive filmmakers, “Entanglement,” this could easily become a quirkfest with Hanna simply serving as a cure-all for what ails Ben, but Filiatrault and Jones use the expectations created by so many films before to construct a touching exploration of mental health as they rise to the challenge of articulating how Ben’s internal logic, which is sound yet idealized, doesn’t line up with the messiness of reality.

In trying to fit itself into a linear form, “Entanglement” shares some of Ben’s discomfort, occasionally raising bigger questions narratively than it has the answers for, but the ambition throughout is so admirable that you’re moved by the effort and besides, it has a trio of strong actors in Middleditch, Weixler and Bang who are equally adept at radiating charm and gravitas. A wonderfully ethereal score from Andrew Harris captures Ben’s mercurial mood perfectly, fanciful at times and mellow at others, but it is “Entanglement”’s general consistency in capturing a lead character that is anything but that’s most impressive. For all the talk of parallel universes, Filiatrault and Jones have crafted a story that’s particularly poignant for the one we’re all in now.

“Entanglement” does not yet have U.S. distribution. It will play once more at the Seattle Film Festival on May 24th at Lincoln Square at 9:15 pm and at the Brooklyn Film Festival on June 2nd at 8:30 pm at the Wythe Hotel and June 7th at the NY Media Center.