Sicilian mafia boss Matteo Messina Denaro is finally behind bars, after 30 years on the run. This week Nexus finds out the inside story behind his arrest, speaking to former mafia boss Marisa Merico. She tells us about life running the family business. We also hear from Edoardo Zaffuto, who founded an Anti-Mafia organisation, and Felia Allum, an expert on organised crime.