He is the worst serial killer in Russia's history.

He just liked to kill.

His rise are very unpleasant. He has the look of a cornered predator.

For years he kept a city in fear.

For years he taunted the police.

We just wanted to catch him to stop people being killed.

He preyed on the lonely and vulnerable.

He operated very, very, very carefully.

And he kept a unique record of his crimes.

Based on unprecedented access to Moscow's elite murder squad and unique police

footage of a disturbing reenacted confession. This is the untold story of the hunt for Russia's most prolific serial killer. Moscow has experienced extraordinary changes since the dark days of the Cold War.

Today it's a place of fabulous wealth and grinding poverty.

Of postcard cathedrals and tough housing estates and it's also

the backdrop for the most notorious serial killer in Russian history.

Bitza Park is an extensive wooded area covering 22 square kilometers of southern Moscow.

It's a popular spot where ordinary Russians play chess or just enjoy a pleasant stroll.

But for years it hid a grisly secret.

On Saturday, October the 15, 2005,

Moscow police find the dead body of 31-year-old Nikolai Warovia.

He suffered terrible injuries to the head.

Dennis Adamenko was one of the first policemen on the scene.

It was here exactly at this place where we found one of the victims. Of course, when we found you, it wasn't a pleasant sight.

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