The gambling mecca Sin City plays host to 40 million tourists a year. In storm drains beneath the Las Vegas strip, homeless addicts get high on crack in underground shanties, while in half-built suburbs, police battle marijuana gangs for control of the city's slump-hit homes.

New York City is in the grip of a heroin epidemic, as a new generation of middle-class suburbanite dealers hooked on prescription pills switch to heroin, and venture down the Long Island Expressway Â- dubbed the Heroin Highway into urban Brooklyn and Queens to get their fix.

Alaska has a dark secret : it has one of the biggest drug problems in America. We'll get a firsthand look at the effects of heroin and the withdrawal symptoms involved in using the drug.

In Hawaii, which has one of the highest rates of crystal meth users in the nation, National Geographic Channel cameras follow along on a raid to a drug trafficker's house to discover a woman who continues to deal crystal meth while her husband is in jail.

The devastating consequences of Hurricane Katrina in Louisiana resulted in a wave of small-scale drug dealers taking over the streets of New Orleans. As a means of coping with depression and post-traumatic stress disorder, traumatized locals have turned to cocaine.

Mexican and Canadian drug gangs compete for customers in the isolated terrain in Montana as officers patrol the vast region hoping to stem the tide.

Heroin, cocaine and prescription pills in plentiful supply makes Los Angeles one of the biggest drug distribution hubs in the U.S.

The local drug scene casts a dark shadow on the sunny lifestyle of Puerto Rico, a place where addicts roam the streets in search of their next fix. For Dr. Panelli, treating abusers for jungle rot,Â"a ghastly condition that comes with using injected drugs, can be an overwhelming task.

The most dangerous city in the USA, Detroit, is a perfect mark for today's growing drug industry. Dealers are learning cater to inner city clientele by selling smaller amounts of hard drugs like heroin and cocaine for single-digit prices.

Cocaine and marijuana drug fueled 24-hour lifestyle for Londoners.