The arrest of the man believed to be the head of the Sicilian mafia this month is the latest blow for an organisation struggling to rebuild after the death last year of Salvatore Riina, the ‘boss of the bosses’. Clare Longrigg, the author of several books on the mafia, describes the current state of Cosa Nostra. Plus: Jonathan Watts on what to take from the COP24 climate talks

When the Sicilian mafia’s ‘boss of bosses’ Salvatore Riina died in an Italian prison last year it marked the end of a chapter for Cosa Nostra. Since then, about 4,000 people with links to the mafia have been arrested and hundreds of millions of euros confiscated. This month, Italian police arrested Settimo Mineo, the 80-year-old believed to be the mafia’s current head.

In today’s show, Anushka Asthana is joined by the Guardian’s Clare Longrigg, the author of several books on the Sicilian mafia. She charts the organised crime syndicate from its peak to the present day.

Plus: the Guardian’s environment editor, Jonathan Watts, on what to take from the COP24 climate talks.