Complex sentence: Whilst Nick the Crow was in prison, Nicky Scarfo began talking of arranging his murder to avoid indictment himself, but a friend of Nick's warned him that Scarfo was mad at him.
Split into simpler sentences: Whilst Nick the Crow was in prison Nicky Scarfo began talking of arranging his murder to avoid indictment himself. But a friend of Nick's warned him that Scarfo was mad at him.