'Do you realise how much strength is needed to strangle a man?" asked Francesco Marino Mannoia. The magistrate listened carefully. "It can take as long as 10 minutes," Marino Mannoia went on, "and sometimes the victim slips out, bites and kicks. Some even manage to break free for a while. But at least it's a professional way of doing the job." This witness was genuine, magistrate Giovanni Falcone decided after listening to such insights into life in the Sicilian mafia. He considered Marino Mannoia an exceptionally bright and honest pentito - the Italian term for a mafioso who turns informant...