Ted Bundy, Charles Manson, David Berkowitz – these men were notorious killers. But were they born bad?

In the hunt for morality, Horizon meets the scientists looking inside the minds of criminals to find out what makes their brains different. If you start out life with parts of your moral machinery broken, how likely are you to have a psychotic destiny? Could “defective moral hard-wiring” be used as a defence in court? And what would it take for things to fall out of balance in our “normal” brains? Could we all become natural born killers?

Horizon finds out just how delicately balanced our brains are.

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