Heroin is a fascinating drug to most people. It is often referred to as the "hardest drug." By this logic, people might start with alcohol, work up to marijuana and maybe LSD. Then they reach to cocaine or methamphetamine. And finally, at the end of the journey is heroin. But like most things about heroin, this is more myth than reality.

For non-users, this mythic power is exciting. And writers for the last century have been more than willing to pander to such readers in pulp and art novels all the way up to television crime novels. But it is rare for the most people to get a real look at...