A professional killer is at large in the cities of Italy. Code-named 'Pit Bull', he is a master of disguise and an expert with weapons. He modifies his guns and his bullets are untraceable. His skill with prosthetics, wigs and makeup means that no two victims witness the same terrifying final vision. This is a hunt for a man with no face. Only the picture of a pit bull terrier left behind at each murder can link the crimes. Day after day, Ispettore Negro works on her seemingly impossible case.
A serial killer is terrorising the people of Bologna, and rookie Detective Inspector Grazia Negro is determined to solve the case. She only has one witness who can identify the killer - and he is blind. Simone spends his nights listening to Chet Baker and scanning the radio waves of the city, eavesdropping on other people's lives. He imagines what people are like - based on the 'colour' of their voice - and his acute hearing sets alarm bells ringing when he tunes in to the killer.