Plot: Cachitos de hierro y cromo is a Spanish musical-themed documentary program, directed by Jero Rodríguez and hosted by Virginia Díaz. It is an unapologetic musical display of RTVE's sound legacy in the form of performances on the set of programs such as 'Aplauso', 'Galas del Sábado', 'Mapa Sonoro', 'Zona Franca' or 'Los Conciertos de Radio 3'