If you don’t blink, Stephen Dietz’s Becky’s New Car makes for an entertaining evening. Blink, however, or pause for reflection, and how and why things happen would perplex even the most gullible among ­us.

Maybe it’s the times, but when I watch movies and see lapses in logic or unreal plot contrivances, I find myself writing plausible back-stories. As in: when she ran from the exploding embassy, she didn’t have the dossier. But now, as she stands up and dusts herself off, the dossier’s back in her left hand. What gives? Okay, you say, so maybe she had a top-secret black ops backpack invisible to the untrained eye. Yeah — and at the last second, she stuffed the dossier in it. That’s the ticket! — and by the time the discontinuity’s accounted for, the movie’s made more perplexing non ­sequiturs.

Except for one key line, Becky’s New Car would make more sense if it were presented as a dream. The coincidences are so blatant you’d swear that only seven people inhabit the ­planet.

Becky Foster’s a title check and office manager for Bill Buckley’s auto dealership in “an American city very much like Seattle.” She’s swamped at work and bogged down at home. Her husband of 27 years, Joe, is a roofer (who won’t fix a leak in theirs), and her 26-year-old son Chris is a grad student still living with his parents. He’s studying psychology and analyzes his parents’ behavior. Referencing Erik Erikson’s Childhood and Society, Chris says his mother has a typical midlife urge to do something productive, for ­once.

In a scene reminiscent of Craig Lucas’s mystic/realistic Prelude to a Kiss or Reckless, Becky gets her chance. Late one night at the office, an elegantly clothed, soft-spoken man appears, wanting to buy a car. Well, not just one; he wants cars for nine employees. He’s not good with gifts, he confesses with arresting modesty. His late wife Sheila took care of such ­things.

It turns out he’s the Walter Flood, owner of almost every billboard in America. As Bones says in Star Trek, Walter has “wealth beyond the dreams of avarice.” He’s so rich he can’t decide between taking the helicopter or the Learjet. And he’s kind and he’s sensitive, and if ever there were a Prince Charming, he’s it. At least from ­afar.

Walter knocks Becky off kilter. He seems to be everything her husband isn’t — which, it turns out, is true, though not as she anticipated. All she must do is stifle one word — “married” — and her adventure/affair ­begins.

The play, and portions of the North Coast Rep production, has gaps. But Mark Pinter’s portrayal of Walter is spot on. Like the character Bruce in Annie Weisman’s Surf Report, at La Jolla Playhouse, with Walter what you see is more than what you get. Both men have been micromanaged for decades and have nary a clue about daily living. Dressed in designer Sonia Lerner’s elegant grays, Pinter gives Walter a mind replete with uncharted territories. He deftly underplays reactions a lesser actor would milk (“They deliver pizza to your home? Really…?”). Were Becky to extend her relationship with Walter, she’d move from lover to mother in short ­shrift.

In effect, the playwright turns Craig Lucas’s mystical dramas on their ear: somber reality lurks behind the fantasy. Even dreams, if acted out, have consequences: you can’t bookmark the departure and, later, return to the pre-tipping ­point.

The North Coast Rep production could pay more attention to these tonal differences. Director David Ellenstein stages most scenes with a smile. This choice works until the second act’s emotional bills, potentially quite dramatic, come ­due.

The choice slights Nicholas Glaeser’s expert performance as Becky’s husband Joe. Like Walter, at first Joe isn’t what he seems. He begins as a couch potato cliché but adds dimensions in Act Two. Glaeser slyly shows that Joe has had a “big, Soviet-style heart” all ­along.

As another minor character with a major-league arc, Glynn Bedington’s a treat as sloshy-drunk, nouveau-broke Ginger: on-the-make mad, in the beginning, she develops “character” before our eyes. Stacey Hardke, Mueen Jahan, and especially Kevin Koppman-Gue (who’s getting good!) make valuable ­contributions.

The play has a problem: it must make a woman about to commit adultery likable. The playwright tries to solve it by having women from the audience come onstage and “participate” (they even vote in favor of Becky’s decision). The traffic to and from house seats not only takes time, it’s an obvious trick to help endear Becky. But Carla Harting, who plays her, has such a natural rapport with the audience — and such an impressive, moment-to-moment focus — that all the pseudo-support just gets in the way of a fascinating ­performance. ■

Becky’s New Car by Stephen Dietz
North Coast Repertory Theatre, 987-D Lomas Santa Fe Drive, Solana Beach
Directed by David Ellenstein; cast: Carla Harting, Nicholas Glaeser, Kevin Koppman-Gue, Mark Pinter, Stacey Hardke, Mueen Jahan, Glynn Bedington; scenic design, Marty Burnett; costumes, Sonia Lerner; lighting, Matt Novotny; sound, Chris Luessmann
Playing through September 26; Wednesday at 7:00 p.m. Thursday through Saturday at 8:00 p.m. Sunday at 7:00 p.m. Matinee Sunday at 2:00 p.m. 858-481-1055.