When Constable Evan Evans is persuaded to join the local male choir for the upcoming eisteddfod (cultural festival), he doesn't think the addition of his mediocre voice will do them much good. In spite of all the effort that choirmaster Mostyn Phillips puts in to the choir, it is not exactly first class. Hope arrives in the form of world renowned tenor Ifor Llewelyn, come home to Llanfair to rest, on doctor's orders.