SERIAL killers are one of the most fascinating and spoken about facets of the true crime genre. But what makes a murderer and why are we so interested in their dark and twisted minds?

Crime World's Clodagh Meaney talks to psychologist and crime commentator Emma Kenny about what makes a serial killer, what victims they prefer and her brand new live show The Serial Killer Next Door.

Crime World, with Nicola Tallant, is a weekly Iri…