The 24th century: humankind has become a spacefaring civilization, colonizing the solar system and beyond. While no alien forms of complex life have yet been found, colonists suddenly encounter machines of alien origin - huge robots able to reproduce themselves. Called replicators by the colonists, they seem to have but a single goal: to destroy all organic life they come in contact with. Since the colonial governments have no means to fight this menace directly, they instead promise huge rewards to whoever destroys a replicator. In the year 2326, about 30 years after the events described in The Frontier: Book 1 of The Hunters' saga, in which humankind discovered the first replicator, the frontier has attracted a new kind of adventurers, the Hunters, who work to find and destroy the replicators. Mike Edwards, a skilled young maintenance technician and robotics expert at a faraway outpost, will not only become one of them - but be the very first one to unlock the secret behind the replicators' origin and mission. He falls in love with Ann, the only human girl of the brothel of the station. When the Hunter's ship docks at the station, Mike convinces the captain to take him in the hunting ship's crew. The hunt is successful, and the Hunter is so satisfied with Mike's work that offers him a permanent job in his crew. When Mike, now a fairly rich man, gets back to the station, he asks Ann to marry him, but she will never be the wife of a hunter, an adventurer who wanders between the stars, risking his life at each encounter. Disappointed, Mike buys one of the robot girls, with the aim of reprogramming her, transforming her in a conscious being, a true woman, and leaves with the Hunter. Like the legendary Pygmalion, he falls in love with her, forgetting Ann. But things turn sour and a replicator destroys an agricultural colony, damaging the Hunter's ship and threatening to destroy the space station where Ann lives. Mike has to make a hard choice between his dreams and his love. From the back cover Is it possible to transform Lulu, an attractive robotic girl, into a deadly weapon to fight against a replicator, one of those self-replicating machines imagined by Von Neumann, able to colonize the universe, destroying any organic life form? Mike succeeds, and he does so because he loves Ann, a very human girl. Entering the belly of the replicator, he takes control of the monster... This looks like a happy ending, but... Darwin would appreciate the evolution theory applied to machines. And if Melville lived today, this would be his Moby Dick. Piero Bianucci, former director of the science pages of La Stampa.