Do humans have an innate sense of morality? If so, where does it exist in the brain and how did it get there? BBC’s Horizon shows how scientists looking into the minds of babies and criminals are rewriting our ideas of right and wrong.

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.

If you would like to comment on this video or anything else you have seen on Future, head over to our Facebook or Google+ page, or message us on Twitter.

Around the BBC