Line of Duty is a police television series produced by the BBC over several seasons, which began in 2012. I borrowed this title in a playful, postmodern context. In fact, the duty that Nomen Est Omen has assumed is to promote medieval music, not to reduce crime. Our means are, in fact, exclusively cultural. We don’t know if the historical pieces we continue to perform, in the good tradition of the musicians of the past, can make the world better, but it certainly makes it more beautiful. Authenticity and historical landmarks are also a form of struggle, but with unseen enemies, such as ignorance and aberration. However, we leave the struggles to the actors and groups of historical reconstructions, going by the idea of the beauty and intrinsic value of music, certainly the most universal language.