The year is 1997. During a Mediterranean cruise, four top businessmen set themselves the challenge of creating a marvellous, unique and inimitable object, out of the reach of even the richest person. Months later, when detective Fermín Escartín is invited to the world presentation of the Amsterdam Solitaire fountain pen, he does not realise that he is becoming involved in a sophisticated corporate revenge, which will take us from the port of Montecarlo to Amsterdam, the world diamond capital, and, of course, to Escartín's native territory in Zaragoza's old town. Thus, there are not always crimes and murders in the life of the Aragonese investigator, as on this occasion he will face the challenge of solving an impeccable, almost perfect, and seemingly impossible robbery.