Even a pulpy end-of-days movie requires a shred of plausibility to avoid becoming an unintentional joke. But “Knowing” is so silly that it not only strains credulity—it shatters it and then stomps it into infinitesimal pieces. If you can get through the picture without suppressing a guffaw or two, you’re a better man than I. And if you can figure out the logic of the plot in retrospect, you deserve some sort of prize.

The whopper of a tale begins fifty years ago, when a troubled little girl named Lucinda (Lara Robinson), who hears strange voices, deposits her contribution to the school time capsule: a page covered with lines of numbers. Five decsades later, her message is opened by tyke Caleb Koestler (Chandler Canterbury), a sad-faced kid who’s grieving the death of his mother. So’s his father John (Nicolas Cage), an MIT astrophysicist estranged from his own father, a minister (Alan Hopgood).

John notices something peculiar about the page of numbers—they seem to prophesy disasters, including 9/11. And three of them are yet to happen. John becomes obsessed with investigating the odd phenomenon (and perhaps preventing the upcoming tragedies)—earning the bewilderment of his colleague Phil (Ben Mendelsohn)—an effort that leads him to contact the deceased Lucinda’s daughter Diana (Rose Byrne), who has fears of her own, and her little daughter Abby (Robinson again). Meanwhile Caleb is approached by a bevy of strange spectral men who give him a smooth black stone and show him a scary vision of overwhelming destruction.

By the close of “Knowing,” there’s a kind of method to all this, but it’s a method that seems quite mad. One doesn’t want to reveal too much about the details, but suffice it to say the movie turns out to be a doomsday thriller with a weirdly redemptive coda that, from this man’s perspective, makes very little sense. The hook, of course, is the page of numbers, which suggests some numerological implication but really doesn’t have any, because in the end the numbers have no symbolic significance: they’re simply a list. But then one has to connect the paper to those spectral men, whom Abby calls The Whisperers, and perhaps ask yourself why they act in so ludicrously labyrinthine a fashion in response to knowledge about coming events that they apparently had fifty years earlier and intend to do something about. The identity of these fellows is also an issue. At some points they seem to be endowed with religious significance—there are stray allusions to faith along the way—but that turns out to be pretty much a red herring. (If what happens at the end is the rapture, it turns out to be a very small event, unless you assume that the story we see is just one of many similar ones—a possibility that increases the absurdity exponentially).

Indeed, the scenario devised by Ryne Douglas Pearson (who came up with the story and then co-wrote a script with Juliet Snowden and Stiles White which director Alex Proyas then “adapted”) ends up seeming overstuffed with undercooked ideas, and fashioned at some points simply to allow for big disaster sequences—a plane crash, a subway accident—that might be more impressive if the CGI effects weren’t so mediocre. They don’t help matters in the last fifteen minutes, either—which are so lugubriously staged that the tacky imagery is italicized.

Through it all Cage plays Koestler as intense and stricken, which becomes a bit boring over the long haul and makes the character’s occasional bursts into action mode rather difficult to believe. More problematic is his chemistry with young Canterbury, which never comes across as convincingly parental, particularly because Proyas’ direction of the boy seems lax, and the bond between father and son feels more formal than real. (That’s the case with John’s relationship with his father, too.) Byrne, meanwhile, is hobbled by a role that’s poorly written and ill-defined, and stuck with a concluding emotional sequence that’s misjudged. But while Mendelssohn is wasted in a thankless part, young Robinson does nicely in her dual role, and as John’s sister Nadia Townsend adds a welcome note of vibrancy to an otherwise pretty dour tale.

You have to give “Knowing” points for Simon Duggan’s cinematography, which creates a suitably creepy atmosphere in the more intimate moments, but those sub-standard effects intrude to cheapen the mood at too many turns, and Richard Learoyd’s editing is often pedestrian. Even worse is Marco Beltrami’s score, which pushes way too hard throughout and makes the mistake of using the second movement of Beethoven’s Seventh Symphony at a couple of important points. That’s mood-breaking.

Ultimately “Knowing” is a typical example of Proyas’ approach (“The Crow,” “Dark City,” “I, Robot”): half-pulp and half effects showcase, with an unconvincing veneer of seriousness. In this case more than most, the result is ridiculous rather than compelling.