Five notorious inmates reveal insights into their predatory behavior.

Long periods of monotony are broken up by brief moments of terror.

Adapting to life in American prisons.

In a life full of restrictions, we've seen inmates take control of whatever they can, despite the consequences. We've seen frustrated inmates reach their breaking point. And in the battle of wills, some will take actions that can never be reversed.

Every murder has a motive and often the murder is committed by the least likely person.

Three inmates prepare to cross the threshold to freedom.

The most extreme Lockup stories ever. These are the prison stories best described by one word. And the word is... HARDCORE.

In prison, as on the outside, a single decision can change a persons life forever. And we've seen inmates make all kinds of fateful choices. But behind bars, there is no escaping the consequences of one's actions.