A couple of skinny teens, stripped to their underwear, unleash a reckless storm of automatic weapons fire - weapons they've jacked from local criminals - just for laughs. In Gomorrah, these kids, Marco (Marco Macor) and Ciro, a.k.a. Piselli (Ciro Petrone), walk around playing bad guys, snorting coke, quoting Al Pacino in Scarface, and brazenly, stupidly, crossing paths with the Camorra crime clan - the real thugs who run Naples.

Marco and Piselli supply but one plot strand in Italian filmmaker Matteo Garrone's searing, documentary-like adaptation of Roberto Saviano's expose about the Naples mafia - gangs whose influence infests the community and the country at large.

A frightening portrait of corruption, cynicism, intimidation, greed and violence, Gomorrah is tough stuff. From the matter-of-fact brutality of its opening scene - the murder of foot soldiers in a tanning salon - to the horrific sequences that take place in an illegal toxic dump, the film brings a coldblooded perspective to a coldblooded business.

The violence isn't glamorized, or glorified. It just is.

Using a cast of mostly nonprofessional actors, Garrone moves his cameras across the cityscape, zooming in on an ugly concrete honeycomb of welfare apartments where a mild-mannered Camorra money runner (Gianfelice Imparato) pays off the family members of mobsters doing time, and where a scrappy 13-year-old (Salvatore Abruzzese) runs errands for the local bosses.

Like David Simon's The Wire, Garrone's film shows the school-age drug dealers guarding their corners, and the kingpins counting their cash. And the film shows how it all interconnects - the drugs, the guns, the waste disposal business, even a million-dollar counterfeit couture operation - in insidious, cancerous ways.

Savian's nonfiction book was a huge best seller - and hugely controversial - in his homeland. The author was provided with bodyguards after Gomorrah was published. After all, the Camorra had reportedly murdered more than 4,000 people over the previous three decades. What's one more body?

From strip clubs to sweatshops to abandoned quarries turned into dumping grounds for chemical poisons, the picture of Italy that emerges from Gomorrah is not one that the tourist boards would want us to see.

But it is one that shows how lawlessness itself can become an institutional force, pervading the culture at every level.

It's ugly. It's powerful. But it's hard to look away.EndText

Contact movie critic Steven Rea at 215-854-5629 or srea@phillynews.com. Read his blog, "On Movies Online," at http://go.philly.com/onmovies.