Since Jack Finney’s “The Body Snatchers” was first published 70 years ago, screen adaptations — official and unofficial alike — have taken place in small-town USA, Me Decade San Francisco, a military base, high school and so forth. All had a gist in common: humanity being infiltrated and co-opted by a shape-shifting invasive force from outer space. Loosely playing on that theme, Zach Clark ’s “ The Becomers ” adds a new wrinkle, in that this time the body-hopping entities don’t necessarily intend conquest.

They just want to co-exist, peacefully. But it turns out they may have chosen the wrong planet and/or species, because they discover today’s mankind is perhaps too messed up to be worth the trouble. That’s a good premise for the kind of sly, deadpan absurdism Clark aims for here.

But despite its fantastical hook, this episodic narrative lands short of the curiously winsome black comedy quirkiness its writer-director achieved with prior features “Little Sister” and “White Reindeer.” A sort of shaggy dog story whose appeal wanes as one gradually realizes it’s unlikely to go anywhere in particular, “The Becomers” is equally mild as sci-fi, spoof and sociopolitical satire. It’s off-kilter enough to catch one’s attention, but in the end too underdeveloped to strongly reward it.

Russell Mael of the long-running cult band Sparks commences things with voiceover narration as our nameless, genderless protagonist, relating a backstory — though.