Like all laboratory rats, Pedro is a rattus norvegicus for more or less close vivisection. But his name is Pedro, and for a Norwegian rat it's already a problem. From his cage, the rodent observes the wanderings and disappointments of the heterogeneous visitors of his cellar, in the basement of a pharmaceutical lab. Pedro lives his life as an animal ready for all experiments even the most stupid, under the scrutiny of a band of labors and preachers preachers, more worried about whether Pedro is Spanish or Norwegian than to carry out any experience scientist. And Pedro has a certain sense of autonomy. And the musical ear, too.