When a movie hangs on a twist, it better be a good one.

The film builds up, hoping to wow the audience with a reversal or stunning revelation that will make the entire cinematic worthwhile. But the cardinal sin of thrillers, or in this case a science-fiction thriller, is predictability.

Unfortunately “Knowing,” the new special-effects blockbuster starring Nicolas Cage, would be better off entitled “Knowing the Ending Before it Happens.”

The film is a poorly acted jumble that goes from disaster scene to action scene, all the while preparing for an ending that is simultaneously predictable and unsatisfying.

Oh, how the mighty have fallen. Cage, once an A-list actor in Hollywood, has since attached his name to such messes as “The Wicker Man” and “Bangkok Dangerous,” giving performances so bad that they were lampooned on the Internet.

This instance is no different, as Cage meanders through the movie moving from unconscionably boring to laughably exaggerated.

He yells plaintively at times and lowers his voice when delivering such authoritative lines as, “The caves can’t save us” and “How do I stop the end of the world?”

The really problematic part is that Cage is still the best actor in the movie by a long shot.

The rest of the cast of “Knowing” is populated by no-names, aside from the bland female counterpart played by Rose Byrne, who somehow manages to make the idea of being able to see the future uninteresting.

The child-acting in the film bucks the trend of recent Hollywood productions that have shown marked improvement. The child actors Chandler Canterbury and Lara Robinson showcase zero talent in “Knowing.”

Outside of Cage, the cast can be summed up in one word: lifeless.

Then again, the direction and dialogue of “Knowing” do not do the actors any favors either.

This is a script that does not seem to have bought into the idea of having actors talk like people living in the real world, and, as a result, it is just line after line of plot advancement.

It takes economy of words to a fault, and unfortunately, this helps give away the ending pretty easily to an attentive viewer.

That said, there are some action scenes that manage to come off the screen and wow an audience member, but the grotesque nature of them will likely evoke nausea, not rapt attention.

“Knowing” seems to have an over-fascination with showing things burn to death, which is not at all fun to watch play out on screen.

If that were not all, there’s a New York disaster scene that shows death after death for no particular reason.

The visuals are technically impressive and aesthetically horrible, using the wonders of CGI to deliver realism where tact and subtlety would do so much more.

The plot of “Knowing” is built around the twist ending, though, and ultimately that is where one’s satisfaction or dissatisfaction with the movie will almost certainly lie.

Sadly, the script and director give too many hints that make the twist easy to figure out.

Anyone with a working knowledge of the Bible will probably see it coming a mile away.

Even without that foreknowledge, it will not blindside anyone.

The best case scenario is moderate intrigue, but it is possible to guess the ending accurately around the 10-minute mark of this two hour film thanks to director Alex Proyas’ hints.

“Knowing” has many of the makings of an exciting thriller.

It has a big name actor, technically accomplished special effects and the underpinnings of a decent twist. However, the movie fails to execute well in nearly every area, creating a long, mostly boring romp with what’s left of Cage’s career.

Even if the twist works for the viewer the odds are the trip to get there will be bumpy, and not in a good way.