Watch National Geographic Documentaries online: Episode 45 Russia's Toughest Prisons

For the first time, three prisons across Russia unlock their doors to an international film crew. From a Siberian prison camp where temperatures plummet to 50 below to the highest security prison, where cannibals, terrorists and serial killers will live out the rest of their days, caged like animals. And, a pass inside infamous Vladimir Central — at over 200 years old, it’s held an estimated one million inmates. Inside Black Dolphin, a cannibal talks openly about his crime, divulging how he boiled, fried and ate his murder victim. In Vladimir Central, a convict opens up about killing his brother-in-law for disturbing his daughter’s peaceful night’s sleep. And inside a Siberian prison camp, we meet two friends about to go their separate ways when one gets paroled.

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