If water naturally gravitates toward the lowest point it can find, then perhaps with "The Happening," M. Night Shyamalan has reached his true depth as a filmmaker.

The would-be cinematic messiah, Mr. Message-in-a-Spooky-Movie, has at long last made the journey from high-brow Philadelphia, his home, to working-class Pittsburgh, where George A. Romero presides. After the heights of "Sixth Sense" and the silliness of "Signs," Night has made his first zombie movie, a zombie movie masquerading as a cautionary tale about a planet in peril.

It starts in Central Park when people freeze up, maybe take a step or two backward, then find something at hand that lets them kill themselves.

Despite being New Yorkers, people notice this behavior as odd. It's "a terrorist attack," "an event," or maybe even a "happening."

Construction workers take the plunge. Tree surgeons hang themselves from their work. Cops eat their pistols and others pick up the gun, passing it on, one bullet, one suicide, at a time.

Chilling stuff. Elliott Moore (Mark Wahlberg), a Philadelphia science teacher, wants to understand. He needs to know why this started in open spaces, why it seems to be spreading in ways that don't suggest "terror attack," and maybe what the mass disappearance of honeybees has to do with it. He needs to get his wife (Zooey Deschanel) and friend Julian (John Leguizamo) out of town.

"I need out of this nightmare."

Shyamalan sends the trio (with pal Julian's daughter, woodenly played by Ashlyn Sanchez) on to a train, a lifeboat fleeing the sinking city. Only it doesn't get far. They're on foot, separated, caught up with other survivors who exchange horrible news and wacky theories about what's going on — crazy people, confused people, grieving people.

Shyamalan scatters overheard radio chat shows and TV interviews with some of the worst "performances" by people supposed to be academics that you'll ever see. The guy who made "faith" and "belief" central to virtually every film he's ever made is a tad too caught up in explaining the unexplainable here.

But pathos sneaks in, in a mom hearing her daughter die by cell phone, in Julian's angry, desperate warning to Elliott's flaky, might-be-cheating wife when he gives her his little girl to protect.

"Don't take my daughter's hand unless you mean it!"

The pacing is fine, and the on-the-road confusion and paranoia work some of the time. But the plot is absurdly preachy and illogical, and the dialogue uneven, with stinging lines followed by stinkers.

"We can't just stand here as uninvolved bystanders!"

Only the voices inside Night's head talk like that. Real people? Not so much.

And yes, we can watch as uninvolved bystanders. We're all a witness to a career that was overpraised until it imploded. At least he's not acting in his movies any more. And at least he hasn't made another one as laughable as "Lady in the Water."

The new Spielberg? The new Hitchcock? Naah. He's the new Romero.