This paper deals with the early years of the so-called Catalan Structuralist School of Molecular Biology led by Joan Antoni Subirana and Jaume Palau. How this period does have been studied? The main secondary sources have been the historiography of Molecular Biology in order to place the subject in an international context and also the historiography of Spanish Molecular Biology. In order to contextualize the research topics, reviews dating from the same years have been consulted. These sources, together with their correspondence, the interviews and the characters own written narrative provided the framework which allowed explaining this story.