Aurelio Zen of Rome's elite Criminalpol is back, but nobody's supposed to know it. After months in hospital recovering from a bomb attack on his car, he is lying low under a false name at a beach resort on the Tuscan coast, waiting to testify in an imminent anti-Mafia trial. Zen has clear instructions: to sit back and enjoy the classic Italian beach holiday - lying in the sun in his assigned chair on a well-managed strip of pale sand, eating seafood and engaging in a little mild flirtation with the attractive woman sitting under the next umbrella. But Zen is getting restless, and as an alarming number of people are dropping dead around him, it seems just a matter of time before the Mafia manage to finish the job they bungled months before on a lonely Sicilian road.

Abruptly, the pleasant monotony of beach life is cut short as Zen finds himself transported to a strange world far from home, and wherever he goes, trouble follows. He must rely on his highly developed survival skills and his innate ability to navigate treacherous waters in order to stay alive.