The narrative of the young boy in Caradog Prichard's semi-autobiographical novel has a dreamlike quality, mingling scenes from his native village of Bethesda in North Wales with it's surroundings in the years leading up to and during the First World War. Central to the boy's life is the figure of his Mam, whose mental decline and subsequent confinement in Denby Asylum forms the central crisis of the novel. In these musical scenes, whose texts are drawn from Prichard's novel, he recalls the mysterious Queen Of The Black Lake; his Mam's poignant singing of the Welsh hymn Cyfammod; her description of a Welsh Revivalist meeting; the Sunday in church when a young pregnant woman is refused Communion; Mam's decline and journey to Denby Asylum; his return to the Black Lake and farewell to it's mysterious Queen.