BBC News, Russia
Since the fall of the Taliban regime in 2001, opium production in Afghanistan has risen dramatically. Russia's geographic proximity to the region has made it a huge consumer - sending thousands of Russians to an early grave every year.
Igor is just one of 30,000 Russians who will die from heroin this year
A couple of weeks ago, and three time zones east of Moscow, I sat and watched another mother as she cried over the lifeless body of her 20-year-old son. It felt like an affront being there, intruding on her inconsolable grief.
The reason I was there, the reason she'd let me be there, is that her son, Igor, had been killed by heroin.
It is a sad fact in Russia that men, in particular, go to an early grave. On average a Russian man is lucky to make it to 60.
In the frozen heart of Siberia they die even younger - around 57.
Alcohol is by far the biggest killer. More than half a million Russians drink themselves to death every year.
But since the early 2000s, another killer has been spreading at frightening speed across Russia.
Actually there are two of them, one closely stalking the other. The first is heroin. The second is HIV.
In the US, there are around 800,000 heroin addicts. In the UK, between 200,000 and 300,000.
In Russia, there are now two and a half million.
Why? What makes Russia so different? Perhaps it has something to do with the climate. In a country that spends half the year in gloom, depression is a big problem.
But by far the biggest reason is geography. Take a look at a map of the world and draw a line north from Afghanistan.
The vast bulk of Russia straddles the Eurasian continent from end to end.
We hear a lot about the effects of Afghan heroin on the streets of Europe. But the countries that are really suffering are the ones on Afghanistan's doorstep, places we know little about, and care even less -Tajikistan, Kyrgyzstan, Kazakhstan, and the biggest of all - Russia.
Continue along that line north and you will eventually arrive at the Siberian city of Novokuznetsk.
It was there that I met a remarkable group of young men. Vlad has the shoulders and bull neck of a nightclub bouncer. But today he is training to become a Protestant priest.
He is also a virtual father to 25 young men. Vlad is a former heroin addict, as are all his staff and all the young men in his care.
Among them is an intense young man called Sergei - his face cast in a seemingly permanent frown.
Sergei was one of Novokuznetsk's 30,000 heroin addicts
Sergei gave up heroin about nine months ago. That he was able to - as well as choose a new life - speaks volumes of the work that Vlad and his staff are doing.
Sergei's father was an alcoholic who beat his mother, stole and ended up in prison. He died there from liver failure.
His mother killed herself when Sergei was a teenager. He found her body hanging from a light fitting in the hallway of their flat. By the age of 15, Sergei and his brother were alone, and dealing drugs.
By the age of 20 he was a major heroin dealer. Then in 2007 his brother was killed, beaten to death in a fight with other drug dealers. What was left of Sergei's world collapsed.
"I had buried every single one of my family," he tells me. "I had no more reason to live, I just lay down on a bed and injected and injected."
That is were Vlad found him a year ago, unwashed, surrounded by filth and close to death.
In the last year, his transformation has been extraordinary. Today Sergei is healthy, strong, and even talks of perhaps contacting his long-lost girlfriend.
But he is one of the few.
In the basement of the rehabilitation centre Vlad shows me the drying-out cell. A terribly ill looking young man is slumped on a bed.
"He came in last night - new arrivals stay here for the first two weeks."
I immediately knew what he was talking about - cold turkey. Heroin withdrawal is an extremely traumatic experience. But it is staying off for the long term that is really difficult.
"Half the young men won't make it," Vlad says. "They'll go back to the streets."
It is perhaps not surprising that Vlad and his band of ex-addicts have a rather bleak sense of humour.
They have turned one room in to a workshop, where I found three young men building what I could swear were coffins.
"Why are you building coffins?" I ask, rather surprised.
"We run an undertakers business," Vlad replies, very matter-of-fact.
"An undertakers? Isn't that a bit morbid given what you've all been through?"
"We have to make money somehow, and round here there's never any shortage of business for an undertaker."
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