“La Canción” tells the story, in a fiction series which takes in the main events: the enrolment of real life Artur Caps, an Austrian emigré but king of TVE’s variety shows, to choose the song; the choice of Joan Manuel Serrat, an icon of Catalan dissidence so symbol of Spanish modernity, to sing it; when Serrat pulls out, denied the right to sing “La, la, la” in Catalan, the de...