VANCOUVER -- "I get yelled at a lot by people driving by," says Jason, staring into his coffee cup. They "come down here from the suburbs and from their houses and they treat the people down here as subhuman."

"Down here" is Vancouver's notorious downtown eastside. Years ago, the neighbourhood was known as Skid Row but things have gotten much worse since then. Today, the downtown eastside is infamous for its drug addicts, prostitutes and despair. From these streets 50 women have vanished since the 1980s, and the neighbourhood is Ground Zero for one of the biggest police investigations in Canadian history that has already seen six charges of first-degree murder laid against Robert William Pickton, 52, a Port Coquitlam pig farmer.

"They're like young kids, young men in from wherever looking for a working girl," says Jason. "And they yell at me and throw things at me. It's their night on the town, I guess."

Jason, 29, is a crack addict. Across the diner table, eating a plate of chicken, is Mary, 31, his girlfriend. Later, Mary's friend Brook arrives. They are addicts, too.

All three live for drugs -- to buy them, to use them, to get the money to buy more. "I can easily spend $500 or $600 in a day," says Jason. But "$250 would keep me going. If I space it out I can get by for a day on that."

We are sitting in a downtown diner, stale with cigarette smoke. At the next table, a middle-aged man wearing a black cowboy shirt and a matching stetson hunches over a chess set, his bushy grey beard twitching as he concentrates and grimaces. Everybody calls him Midnight Cowboy. His opponent is the diner's manager, a grey-faced Chinese man.

Jason, Mary and Brook are concentrating, too. On their next fix. Brook is only 23 but she is clearly the most physically damaged of the three. Her elfin face is thin and lined under a ball cap too big for her tiny head. Her blue eyes water, her nose runs. She moves in jerky motions, her words tumble out and snap off in mid-sentence.

"I mostly use heroin," Brook says. "I'm not a crack fiend but I smoke the odd ... " She breaks off, then jerks back into motion. "I spend more money on the heroin addiction because that's why I'm here. It's like it totally rules my ... " Stop. "24/7 it rules me. It's like a controlling boyfriend. It's kind of weird cause it's like a substance ... " Stop. "I'm thinking, after I do a hit of something, I'm thinking already if I have no money what I'm going to do next. Before I even do it."

Mary uses cocaine -- crack or powder -- and heroin, though she says she's quitting heroin. Track marks snake up her arms. One angry line, as thick as my thumb, looks like a white vein streaked through marble. "That's from a gram of powder (cocaine)," she says.

Mary is tiny. Her black hair is short and spiky, her eyes shrouded beneath a thick, black, theatrical smear of eyeliner. Her voice is high and quiet, girlish. She could still pass as the runaway teenager she once was.

Her drugs cost her $300 or $400 a day. To pay for them, she works the downtown eastside hooker stroll, a bleak, dark industrial district next to Vancouver's harbour.

"Sometimes," Mary says, "if I'm really hurting (for drugs) I do a date for $30 or $20." Like all prostitutes, Mary tries to develop regular customers and stick with them. "I do $20 with them sometimes but it's just a hand job or something. It's not like sex or something. And then when they get paid they come back and give me a hundred bucks or two hundred bucks, right? And that's how you keep the same guys all the time. And it's better that way. Safer."

Until recently, Jason, who has been a crack addict for three years, managed to pay for drugs by working at regular jobs. Now, "welfare helps out about one day a month. And the rest of it winds up being crime." He nods his head slowly and adds, "Shoplifting and things like that. I'm not a violent man. I never have been." He recently pawned a Gore-Tex jacket for a few dollars that vanished up a crack pipe, leaving him to endure the cold drizzle in only a sweater.

Jason, Mary and Brook are all homeless but in a sad twist, heavy crack use eases their need for shelter and other basics. Food isn't so important because cocaine suppresses appetite: "You get really skinny. Plus dehydrated, and sometimes eating makes me sick," says Jason.

He ate today and probably will again later. That's why he looks good today, he says. He's undeniably handsome, graced with a warm smile and charm that in a better place and time could be found in the pages of GQ. "But I can look pretty skidded out sometimes, too."

Extreme cocaine consumption can also keep a user awake and wired for days at a time, spawning psychosis and violence. That's how Mary received a two-and-a-half-year prison sentence

"I was shooting cocaine and I'd stayed awake for too long. I was awake for almost a week. I started to hallucinate," she says. "It was raining out and this guy picked me up and he decided he didn't want a date with me after we drove around the block a couple of times, right. I wasn't going to take no for an answer so I pulled out a big serrated bread knife. And I grabbed him by the hair and put it to his throat and I robbed him. And I cut him and I didn't even realize it. I didn't remember doing any of this."

These streets are drenched in violences. Addicts rob hookers. Dealers beat addicts. Bloody-minded johns hunt hookers. Drugs and prostitution generate most of the money here, which is why most in this netherworld see the police as a threat, not protection.

"Police are assholes," Mary says. She has been trying hard not to swear, apologizing demurely whenever she slipped. But not now "they don't give a f--- about us."

A few weeks ago, Mary says, she and a john smoked crack with in his car. When it was finished, he asked for more; she had none. "He goes, well, I'll just take it out of your ass. And he pulls out this great big f---ing hunting knife and he stabbed me right here." Mary points to a knife graze on the side of her chest. "I don't know how I got the door open even, but I ran. I was so scared."

As Mary talks, Jason leaves to find a dealer and buy a few rocks of crack cocaine. Later, when Jason tells his story, Mary will do the same. Brook slips in and out several times. Someone is always in motion, scoring, using, or seeking cash to score again.

For the addict, the constant scramble to get drugs, use drugs and make money for more drugs, all the while avoiding a beating or having your throat slit, is brutally demanding. That is the irony: a fierce work ethic, dedication and intelligence are essential.

"It takes brains to survive on the street," Mary says. "No matter which way you do it. You can be a panhandler or a prostitute or a drug dealer or whatever. It all takes thinking and brains."

They stay only because drugs won't let them leave. A chronic user who stops will go into withdrawal. The experience varies depending on the drug, but it's always brutal. Heroin withdrawal, says Jason, "is like the most extreme flu that you can possibly imagine. You cannot stay awake, you cannot stay asleep and every part of your body hurts. Even your teeth. Even your hair."

Jason talks in detached pop-psychology terms, as if he's analysing someone else. Only when prodded does his detachment fail and he begins to offer, slowly, piece by piece, the source of the emotions that he dulls with crack.

Only then does it become clear that for Jason -- and for Mary and for Brook -- that drugs are not the problem. Beneath the drugs -- the crack, the heroin -- the filthy streets, the prostitution, crime and violence, Skid Row is built on pain.

"My mum was a heroin addict, right," Brook says. "I think of heroin like a disease." Brook's mother, dead since 1996, lived on Vancouver Island and moved in with a man named Tony. "He was short, maybe a little taller than me and curly, curly hair. He look like a clown." She shakes her head. "He used to beat her a lot. My mum was tiny, she was tinier than me. He took a hammer to her, to her head once."

But Brook's mother always went back. Until, when Brook and her twin sister were 11, Tony beat her mother again "and I was mad. Never felt like that before. I hit him over the back of the head (with a piece of wood) and I just grabbed my mum by the shirt." At a neighbour's house, they called the police. "We ended up in a transition house. And then my mother, three days later, after being there, disappeared. And I knew what happened. Obviously, she went back to him."

Brook and her sister were placed in foster homes but when Brook turned 13, she hitchhiked to Calgary.

"I couldn't get a job because I was too small, too young. They wouldn't hire me. After a few days of panhandling the same guy would come to me each day and ask me to do a date. He offered $250." At first she refused, but eventually went with him to a van in an underground parking garage. "I was younger then, more naive, but man I was happy after that. I was in this van for not even five minutes and I had $250."

Two years ago, when she was 21, she found heroin hidden in a boyfriend's bathroom. Before long she became an addict like her mother.

A majority of people who use drugs do not descend into addiction. Only a blighted minority are held in its white-knuckle grip. In almost every case, addicts were in pain long before they discovered drugs. They saw addicted parents. They suffered physical or sexual abuse. From their earliest years, they experienced violence, broken trust, abandonment, mental illness, crime and suicide.

Mary's story begins: "My mother was a heroin addict." Mary is originally from Halifax. She doesn't have much to say about her father. "I remember he taught me how to cook Kraft Dinner. That's the only thing I remember." But she does know he was a "speed freak.

"My mom was, I guess you could call it, looking after me. She'd leave me home a lot, by myself. And she'd go out. She'd leave other guys to babysit me, like her friends, friends that she used with, or her drinking buddies. Or my grandfather. That's how I started using."

When Mary was 11, her mother "left this man, Dave" to babysit. Dave gave her a joint. "It made me happy. It made me feel like nothing could touch me and everything was OK. So I started stealing my mum's drugs."

Of course, she was caught and locked in a closet. "I was in there for almost two days. After that happened, I guess a part of me changed. I didn't care for anybody. I hated the world after that. So I ran away."

Mary was put in foster care. Her mother went to court, promised to stay away from heroin and got her daughter back. "Everything was OK for about a year after that. I would have been about 13 then. And she left my grandfather to babysit me and he raped me. And I ended up pregnant."

Tears spill over Mary's black eyeliner. She lets a little time pass. Her grandfather had abused her before. "But my mother chose to ignore it. Whatever he was doing for her was more important than me. Everything else was always more important than me. Not that I blame them for the way that my life is now. But you start to hate yourself and you think you're no good for anything else. Just to be used."

Mary spent her teenage years taking drugs and paying for them with prostitution. "I had four kids by the time I was 19." All were adopted.

She went to prison for attacking a john and, craving a fresh start, she asked to serve her parole in Vancouver. "I really was sincere, I wanted to change. But wanting it and doing it are two different things."

At first, Jason seems to have arrived on the downtown eastside from a different planet. He says he was born and raised in a Toronto suburb. Went to university. Became a professional dancer. Danced in Toronto and New York City. He met and married a fellow dancer who got a Canada Council grant and they both worked in Europe.

Jason didn't touch a drug until he was 24 and his wife introduced him to marijuana. He immediately started using pot compulsively. He checked himself into rehab, which didn't work so well. "You know how criminals learned to be better criminals in prison? I learned about (hard) drugs in rehab." When he tried crack for the first time his life shattered.

Today, his wife and his two-year-old son live an hour's drive from Vancouver. Jason is reserved and analytical, until he speaks of his son. "It's hard," he says, struggling to talk. "'Daddy come home.' It's rough." He takes a deep breath and exhales. "When I say that I have become something that I have contempt for, a big part of that's not being there for my son."

How did it come to this? Jason offers the details reluctantly and it becomes clear he's not so different than Mary and Brook.

Jason never knew his father. "My mum was 16 and single when I was born. We lived with her parents."

Both of Jason's grandparents were alcoholics. "And my grandmother was addicted to Valium as well." Both grandparents "drank until they died. My grandmother killed herself when I was four. And my grandfather drank until the day of his death.

"I was sexually abused for the first time when I was five. My teacher at school, who was actually a woman." When he was 13, he worked as a volunteer at a nursing home, he says, and "there was a male orderly there who raped me."

Here's what Mary wishes people would understand. "All the drug use and all the grossness they see, there's pain behind all that. It's all pain. We didn't get here because we chose to be here. We got here because we don't want to face our lives. Because people have hurt us all our lives. And the only way I know how to survive is to do drugs. If I don't do drugs, I feel like I'm going to go insane. Because I have all these thoughts and all this pain in my heart and I can't get rid of it, you know. Drugs is the only thing that takes that away. That's why I do drugs. Because it keeps me, not happy, but it keeps me from being so sad that I want to die."

We step onto Skid Row's frigid, rain-slicked streets. Jason and Mary leave to find a dealer. Brook says we can take pictures if we like.

We arrive in a back alley, the sort of black, wet and empty place where johns and hookers do dates.

Brook pours powder cocaine into the reservoir of a needle, adds a little water, shakes the rig to make a milky white liquid. Shooting the powder gives a bigger rush than sniffing, and getting the best bang for the buck is all that matters.

She wraps a rubber tube around her tiny arm and slaps her skin, making the veins bulge as large as the track marks that snake up her arm. She jams in the needle.

Within seconds, she's jerks upright, energized. She stuffs the needle and rubber tube back in her bag and starts off down the alley with eyes wide and arms and legs pumping even more awkwardly.

She snaps her head to the side. "Look at the way you're are looking at me," she says. "You're treating me different."

It doesn't matter what I say. She's wired.

Brook crosses the road in stiff strides and heads for the stroll. She's used what's she's got so she's got to start the whole cycle again.

She won't trust me or anyone else tonight.

Another motivation is the desire to hold power over another person. "Not all interactions between buyers and sellers are about exploitation of power in that way," says Mr. Atchison, "but many of them are."

Det.-Const. Payette says he once stopped a man who "drove a nice new Jaguar. Very nice man. Picking up a prostitute that was the most asexual human being I've ever met. She was (like) a concentration camp victim -- she looked exactly like the photos of the Jewish women at Auschwitz and Dachau."

This very wealthy man, says Det.-Const. Payette, "was bargaining with her. He wanted to pay $15 for sex without a condom but she wanted $20 and he was bargaining with her. I finally asked him, in sheer frustration, because he was really bothering me, 'How much are your socks worth?' He said, 'Around $78.' "

Det.-Const. Payette shakes his head. "That's not about sex. That's about power."

Other, more forgivable motives also lead men to prostitutes. "There are men who go to sex workers for what they describe as some sort of emotional connection, a conversation, or just someone to be with," Mr. Atchison says.

Researchers and police agree johns are not some deviant sub-group. They are, Det.-Const. Payette says, a reflection of the whole community. "But that's not what people want to hear. People want to hear it's all uneducated people or it's all people from bad neighbourhoods. That's not true. We deal with everything in society."

In saying that, he neatly summarizes not just the reality of johns, but the entire commercial sex industry.

Prostitution is not some deviant activity. It is a mirror of all of us. Like the society it reflects, the reality of the sex trade varies from person to person. It is profoundly complex, defying easy stereotypes and, most of all, simple answers.