In an 8th floor apartment in Miami Beach one man raises a spotted hyena, putting himself in mortal danger. In Africa, a schoolteacher wakes to the sound of her own bones crunching as she is dragged away in the vice-like grip of a hyena's jaws.

Sam Mazzola kept bears on his farm in Iowa. He charged people to wrestle them and enjoyed the attention and financial rewards. When a young employee is killed while tending to a savage bear, the dark truth about Sam's destructive lifestyle is revealed.

In 2011, 49 dangerous animals including tigers, lions and bears roamed free in Ohio. The ensuing bloodbath hit headlines across the world. But what drove the man responsible release his exotic pets and how did his addiction to them spiral out of control?